Remove incorrect usage of GTEST_ATTRIBUTE_UNUSED_ on classes.

Fixes: #4054
PiperOrigin-RevId: 488721587
Change-Id: I8742d8475376635c83edcf524796a6107042e89b

Author: Abseil Team

googletest/include/gtest/gtest.h

@@ -2075,9 +2075,7 @@ class GTEST_API_ ScopedTrace {
 
   ScopedTrace(const ScopedTrace&) = delete;
   ScopedTrace& operator=(const ScopedTrace&) = delete;
-} GTEST_ATTRIBUTE_UNUSED_;  // A ScopedTrace object does its job in its
-                            // c'tor and d'tor.  Therefore it doesn't
-                            // need to be used otherwise.
+};
 
 // Causes a trace (including the source file path, the current line
 // number, and the given message) to be included in every test failure

googletest/include/gtest/internal/gtest-death-test-internal.h

@@ -99,7 +99,7 @@ class GTEST_API_ DeathTest {
     DeathTest* const test_;
     ReturnSentinel(const ReturnSentinel&) = delete;
     ReturnSentinel& operator=(const ReturnSentinel&) = delete;
-  } GTEST_ATTRIBUTE_UNUSED_;
+  };
 
   // An enumeration of possible roles that may be taken when a death
   // test is encountered.  EXECUTE means that the death test logic should

googletest/include/gtest/internal/gtest-port.h

@@ -668,17 +668,11 @@ typedef struct _RTL_CRITICAL_SECTION GTEST_CRITICAL_SECTION;
 #define GTEST_HAVE_FEATURE_(x) 0
 #endif
 
-// Use this annotation at the end of a struct/class definition to
-// prevent the compiler from optimizing away instances that are never
-// used.  This is useful when all interesting logic happens inside the
-// c'tor and / or d'tor.  Example:
-//
-//   struct Foo {
-//     Foo() { ... }
-//   } GTEST_ATTRIBUTE_UNUSED_;
-//
-// Also use it after a variable or parameter declaration to tell the
+// Use this annotation after a variable or parameter declaration to tell the
 // compiler the variable/parameter does not have to be used.
+// Example:
+//
+//   GTEST_ATTRIBUTE_UNUSED_ int foo = bar();
 #if GTEST_HAVE_ATTRIBUTE_(unused)
 #define GTEST_ATTRIBUTE_UNUSED_ __attribute__((unused))
 #else

googletest/src/gtest-internal-inl.h

@@ -212,7 +212,7 @@ class GTestFlagSaver {
   int32_t stack_trace_depth_;
   std::string stream_result_to_;
   bool throw_on_failure_;
-} GTEST_ATTRIBUTE_UNUSED_;
+};
 
 // Converts a Unicode code point to a narrow string in UTF-8 encoding.
 // code_point parameter is of type UInt32 because wchar_t may not be