Introduce runtime check that it is root isolate that makes UI native calls.

lib/ui/compositing/scene_builder.cc

@@ -37,6 +37,7 @@
 namespace flutter {
 
 static void SceneBuilder_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&SceneBuilder::create, args);
 }
 

lib/ui/compositing/scene_host.cc

@@ -47,6 +47,7 @@ using SceneHostBindings = std::unordered_map<SceneHostBindingKey,
 static SceneHostBindings scene_host_bindings;
 
 void SceneHost_constructor(Dart_NativeArguments args) {
+  flutter::UIDartState::ThrowIfUIOperationsProhibited();
   tonic::DartCallConstructor(&flutter::SceneHost::Create, args);
 }
 

lib/ui/dart_ui.cc

@@ -42,29 +42,17 @@ namespace flutter {
 namespace {
 
 static tonic::DartLibraryNatives* g_natives;
-static tonic::DartLibraryNatives* g_natives_secondary;
 
 Dart_NativeFunction GetNativeFunction(Dart_Handle name,
                                       int argument_count,
                                       bool* auto_setup_scope) {
   return g_natives->GetNativeFunction(name, argument_count, auto_setup_scope);
 }
 
-Dart_NativeFunction GetNativeFunctionSecondary(Dart_Handle name,
-                                               int argument_count,
-                                               bool* auto_setup_scope) {
-  return g_natives_secondary->GetNativeFunction(name, argument_count,
-                                                auto_setup_scope);
-}
-
 const uint8_t* GetSymbol(Dart_NativeFunction native_function) {
   return g_natives->GetSymbol(native_function);
 }
 
-const uint8_t* GetSymbolSecondary(Dart_NativeFunction native_function) {
-  return g_natives_secondary->GetSymbol(native_function);
-}
-
 }  // namespace
 
 void DartUI::InitForGlobal() {
@@ -97,21 +85,13 @@ void DartUI::InitForGlobal() {
 #if defined(OS_FUCHSIA)
     SceneHost::RegisterNatives(g_natives);
 #endif
-
-    // Secondary isolates do not provide UI-related APIs.
-    g_natives_secondary = new tonic::DartLibraryNatives();
-    DartRuntimeHooks::RegisterNatives(g_natives_secondary);
-    IsolateNameServerNatives::RegisterNatives(g_natives_secondary);
   }
 }
 
-void DartUI::InitForIsolate(bool is_root_isolate) {
+void DartUI::InitForIsolate() {
   FML_DCHECK(g_natives);
-  auto get_native_function =
-      is_root_isolate ? GetNativeFunction : GetNativeFunctionSecondary;
-  auto get_symbol = is_root_isolate ? GetSymbol : GetSymbolSecondary;
   Dart_Handle result = Dart_SetNativeResolver(
-      Dart_LookupLibrary(ToDart("dart:ui")), get_native_function, get_symbol);
+      Dart_LookupLibrary(ToDart("dart:ui")), GetNativeFunction, GetSymbol);
   if (Dart_IsError(result)) {
     Dart_PropagateError(result);
   }

lib/ui/dart_ui.h

@@ -12,7 +12,7 @@ namespace flutter {
 class DartUI {
  public:
   static void InitForGlobal();
-  static void InitForIsolate(bool is_root_isolate);
+  static void InitForIsolate();
 
  private:
   FML_DISALLOW_IMPLICIT_CONSTRUCTORS(DartUI);

lib/ui/painting/canvas.cc

@@ -25,6 +25,7 @@ using tonic::ToDart;
 namespace flutter {
 
 static void Canvas_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&Canvas::Create, args);
 }
 

lib/ui/painting/codec.cc

@@ -145,6 +145,7 @@ static std::variant<ImageDecoder::ImageInfo, std::string> ConvertImageInfo(
 }
 
 static void InstantiateImageCodec(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   Dart_Handle callback_handle = Dart_GetNativeArgument(args, 1);
   if (!Dart_IsClosure(callback_handle)) {
     Dart_SetReturnValue(args, tonic::ToDart("Callback must be a function"));

lib/ui/painting/color_filter.cc

@@ -4,6 +4,7 @@
 
 #include "flutter/lib/ui/painting/color_filter.h"
 
+#include "flutter/lib/ui/ui_dart_state.h"
 #include "third_party/tonic/converter/dart_converter.h"
 #include "third_party/tonic/dart_args.h"
 #include "third_party/tonic/dart_binding_macros.h"
@@ -12,6 +13,7 @@
 namespace flutter {
 
 static void ColorFilter_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&ColorFilter::Create, args);
 }
 

lib/ui/painting/gradient.cc

@@ -17,6 +17,7 @@ typedef CanvasGradient
     Gradient;  // Because the C++ name doesn't match the Dart name.
 
 static void Gradient_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&CanvasGradient::Create, args);
 }
 

lib/ui/painting/image_filter.cc

@@ -16,6 +16,7 @@
 namespace flutter {
 
 static void ImageFilter_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&ImageFilter::Create, args);
 }
 

lib/ui/painting/path.cc

@@ -8,6 +8,7 @@
 #include <math.h>
 
 #include "flutter/lib/ui/painting/matrix.h"
+#include "flutter/lib/ui/ui_dart_state.h"
 #include "third_party/tonic/converter/dart_converter.h"
 #include "third_party/tonic/dart_args.h"
 #include "third_party/tonic/dart_binding_macros.h"
@@ -20,6 +21,7 @@ namespace flutter {
 typedef CanvasPath Path;
 
 static void Path_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&CanvasPath::CreateNew, args);
 }
 

lib/ui/painting/path_measure.cc

@@ -8,6 +8,7 @@
 #include <math.h>
 
 #include "flutter/lib/ui/painting/matrix.h"
+#include "flutter/lib/ui/ui_dart_state.h"
 #include "third_party/tonic/converter/dart_converter.h"
 #include "third_party/tonic/dart_args.h"
 #include "third_party/tonic/dart_binding_macros.h"
@@ -20,6 +21,7 @@ namespace flutter {
 typedef CanvasPathMeasure PathMeasure;
 
 static void PathMeasure_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&CanvasPathMeasure::Create, args);
 }
 

lib/ui/painting/picture_recorder.cc

@@ -14,6 +14,7 @@
 namespace flutter {
 
 static void PictureRecorder_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&PictureRecorder::Create, args);
 }
 

lib/ui/painting/vertices.cc

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "flutter/lib/ui/painting/vertices.h"
+#include "flutter/lib/ui/ui_dart_state.h"
 
 #include <algorithm>
 
@@ -27,6 +28,7 @@ void DecodeInts(const tonic::Int32List& ints, T* out) {
 }  // namespace
 
 static void Vertices_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&Vertices::Create, args);
 }
 

lib/ui/semantics/semantics_update.cc

@@ -7,6 +7,7 @@
 #include <memory>
 
 #include "flutter/lib/ui/painting/matrix.h"
+#include "flutter/lib/ui/ui_dart_state.h"
 #include "third_party/tonic/converter/dart_converter.h"
 #include "third_party/tonic/dart_args.h"
 #include "third_party/tonic/dart_binding_macros.h"

lib/ui/semantics/semantics_update_builder.cc

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "flutter/lib/ui/semantics/semantics_update_builder.h"
+#include "flutter/lib/ui/ui_dart_state.h"
 
 #include "third_party/skia/include/core/SkScalar.h"
 #include "third_party/tonic/converter/dart_converter.h"
@@ -13,6 +14,7 @@
 namespace flutter {
 
 static void SemanticsUpdateBuilder_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&SemanticsUpdateBuilder::create, args);
 }
 

lib/ui/text/font_collection.cc

@@ -39,6 +39,7 @@ void LoadFontFromList(tonic::Uint8List& font_data,
 }
 
 void _LoadFontFromList(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   tonic::DartCallStatic(LoadFontFromList, args);
 }
 

lib/ui/text/paragraph_builder.cc

@@ -130,6 +130,7 @@ const int sForceStrutHeightMask = 1 << sForceStrutHeightIndex;
 }  // namespace
 
 static void ParagraphBuilder_constructor(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   DartCallConstructor(&ParagraphBuilder::create, args);
 }
 

lib/ui/ui_dart_state.cc

@@ -25,7 +25,8 @@ UIDartState::UIDartState(
     std::string advisory_script_entrypoint,
     std::string logger_prefix,
     UnhandledExceptionCallback unhandled_exception_callback,
-    std::shared_ptr<IsolateNameServer> isolate_name_server)
+    std::shared_ptr<IsolateNameServer> isolate_name_server,
+    bool is_root_isolate)
     : task_runners_(std::move(task_runners)),
       add_callback_(std::move(add_callback)),
       remove_callback_(std::move(remove_callback)),
@@ -36,6 +37,7 @@ UIDartState::UIDartState(
       advisory_script_uri_(std::move(advisory_script_uri)),
       advisory_script_entrypoint_(std::move(advisory_script_entrypoint)),
       logger_prefix_(std::move(logger_prefix)),
+      is_root_isolate_(is_root_isolate),
       unhandled_exception_callback_(unhandled_exception_callback),
       isolate_name_server_(std::move(isolate_name_server)) {
   AddOrRemoveTaskObserver(true /* add */);
@@ -62,6 +64,13 @@ void UIDartState::DidSetIsolate() {
   SetDebugName(debug_name.str());
 }
 
+void UIDartState::ThrowIfUIOperationsProhibited() {
+  if (!UIDartState::Current()->IsRootIsolate()) {
+    Dart_ThrowException(
+        tonic::ToDart("UI actions are only available on root isolate."));
+  }
+}
+
 void UIDartState::SetDebugName(const std::string debug_name) {
   debug_name_ = debug_name;
   if (window_)

lib/ui/ui_dart_state.h

@@ -34,6 +34,9 @@ class UIDartState : public tonic::DartState {
   static UIDartState* Current();
 
   Dart_Port main_port() const { return main_port_; }
+  // Root isolate of the VM application
+  bool IsRootIsolate() const { return is_root_isolate_; }
+  static void ThrowIfUIOperationsProhibited();
 
   void SetDebugName(const std::string name);
 
@@ -89,7 +92,8 @@ class UIDartState : public tonic::DartState {
               std::string advisory_script_entrypoint,
               std::string logger_prefix,
               UnhandledExceptionCallback unhandled_exception_callback,
-              std::shared_ptr<IsolateNameServer> isolate_name_server);
+              std::shared_ptr<IsolateNameServer> isolate_name_server,
+              bool is_root_isolate_);
 
   ~UIDartState() override;
 
@@ -113,6 +117,7 @@ class UIDartState : public tonic::DartState {
   const std::string advisory_script_entrypoint_;
   const std::string logger_prefix_;
   Dart_Port main_port_ = ILLEGAL_PORT;
+  const bool is_root_isolate_;
   std::string debug_name_;
   std::unique_ptr<Window> window_;
   tonic::DartMicrotaskQueue microtask_queue_;

lib/ui/window/window.cc

@@ -18,16 +18,19 @@ namespace flutter {
 namespace {
 
 void DefaultRouteName(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   std::string routeName =
       UIDartState::Current()->window()->client()->DefaultRouteName();
   Dart_SetReturnValue(args, tonic::StdStringToDart(routeName));
 }
 
 void ScheduleFrame(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   UIDartState::Current()->window()->client()->ScheduleFrame();
 }
 
 void Render(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   Dart_Handle exception = nullptr;
   Scene* scene =
       tonic::DartConverter<Scene*>::FromArguments(args, 1, exception);
@@ -39,6 +42,7 @@ void Render(Dart_NativeArguments args) {
 }
 
 void UpdateSemantics(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   Dart_Handle exception = nullptr;
   SemanticsUpdate* update =
       tonic::DartConverter<SemanticsUpdate*>::FromArguments(args, 1, exception);
@@ -50,6 +54,7 @@ void UpdateSemantics(Dart_NativeArguments args) {
 }
 
 void SetIsolateDebugName(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   Dart_Handle exception = nullptr;
   const std::string name =
       tonic::DartConverter<std::string>::FromArguments(args, 1, exception);
@@ -61,12 +66,15 @@ void SetIsolateDebugName(Dart_NativeArguments args) {
 }
 
 void SetNeedsReportTimings(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
   Dart_Handle exception = nullptr;
   bool value = tonic::DartConverter<bool>::FromArguments(args, 1, exception);
   UIDartState::Current()->window()->client()->SetNeedsReportTimings(value);
 }
 
 void ReportUnhandledException(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
+
   Dart_Handle exception = nullptr;
 
   auto error_name =
@@ -143,6 +151,8 @@ void _RespondToPlatformMessage(Dart_NativeArguments args) {
 }
 
 void GetPersistentIsolateData(Dart_NativeArguments args) {
+  UIDartState::ThrowIfUIOperationsProhibited();
+
   auto persistent_isolate_data =
       UIDartState::Current()->window()->client()->GetPersistentIsolateData();
 
@@ -270,6 +280,7 @@ void Window::UpdateSemanticsEnabled(bool enabled) {
   if (!dart_state)
     return;
   tonic::DartState::Scope scope(dart_state);
+  UIDartState::ThrowIfUIOperationsProhibited();
 
   tonic::LogIfError(tonic::DartInvokeField(
       library_.value(), "_updateSemanticsEnabled", {tonic::ToDart(enabled)}));

runtime/dart_isolate.cc

@@ -136,8 +136,8 @@ DartIsolate::DartIsolate(const Settings& settings,
                   advisory_script_entrypoint,
                   settings.log_tag,
                   settings.unhandled_exception_callback,
-                  DartVMRef::GetIsolateNameServer()),
-      is_root_isolate_(is_root_isolate),
+                  DartVMRef::GetIsolateNameServer(),
+                  is_root_isolate),
       disable_http_(settings.disable_http) {
   phase_ = Phase::Uninitialized;
 }
@@ -264,7 +264,7 @@ bool DartIsolate::LoadLibraries() {
 
   DartIO::InitForIsolate(disable_http_);
 
-  DartUI::InitForIsolate(IsRootIsolate());
+  DartUI::InitForIsolate();
 
   const bool is_service_isolate = Dart_IsServiceIsolate(isolate());
 

runtime/dart_isolate.h

@@ -381,9 +381,6 @@ class DartIsolate : public UIDartState {
   ///
   fml::RefPtr<fml::TaskRunner> GetMessageHandlingTaskRunner() const;
 
-  // Root isolate of the VM application
-  bool IsRootIsolate() const { return is_root_isolate_; }
-
  private:
   class AutoFireClosure {
    public:
@@ -401,7 +398,6 @@ class DartIsolate : public UIDartState {
   std::vector<std::shared_ptr<const fml::Mapping>> kernel_buffers_;
   std::vector<std::unique_ptr<AutoFireClosure>> shutdown_callbacks_;
   fml::RefPtr<fml::TaskRunner> message_handling_task_runner_;
-  const bool is_root_isolate_;
   const bool disable_http_;
 
   DartIsolate(const Settings& settings,

shell/platform/fuchsia/dart-pkg/zircon/sdk_ext/handle.cc

@@ -163,7 +163,7 @@ void Handle::ScheduleCallback(tonic::DartPersistentValue callback,
   DART_REGISTER_NATIVE_STATIC(CLASS, METHOD),
 
 FOR_EACH_STATIC_BINDING(DART_NATIVE_CALLBACK_STATIC)
-FOR_EACH_BINDING(DART_NATIVE_CALLBACK)
+FOR_EACH_BINDING(DART_NATIVE_NO_UI_CHECK_CALLBACK)
 
 void Handle::RegisterNatives(tonic::DartLibraryNatives* natives) {
   natives->Register({FOR_EACH_STATIC_BINDING(DART_REGISTER_NATIVE_STATIC_)