all: remove trailing whitespace from HTML files

I noticed lots of trailing whitespace in one of cmd/trace's HTML files.
While at it, remove a few others from still-maintained files. Leave old
documents alone, such as doc/devel/weekly.html.

Change-Id: I7de7bbb6dd3fe6403bbb1f1178a8d3640c1e537b
Reviewed-on: https://go-review.googlesource.com/c/go/+/196178
Run-TryBot: Daniel Martí <[email protected]>
TryBot-Result: Gobot Gobot <[email protected]>
Reviewed-by: Brad Fitzpatrick <[email protected]>

Author: mvdan

doc/articles/wiki/index.html

@@ -581,7 +581,7 @@ <h2>Validation</h2>
 
 <p>
 First, add <code>"regexp"</code> to the <code>import</code> list.
-Then we can create a global variable to store our validation 
+Then we can create a global variable to store our validation
 expression:
 </p>
 

doc/gccgo_contribute.html

@@ -105,7 +105,7 @@ <h2>Submitting Changes</h2>
 <p>
 Changes to the Go frontend should follow the same process as for the
 main Go repository, only for the <code>gofrontend</code> project and
-the <code>[email protected]</code> mailing list 
+the <code>[email protected]</code> mailing list
 rather than the <code>go</code> project and the
 <code>[email protected]</code> mailing list.  Those changes
 will then be merged into the GCC sources.

doc/gccgo_install.html

@@ -80,7 +80,7 @@ <h2 id="Source_code">Source code</h2>
 
 <p>
 If you cannot use a release, or prefer to build gccgo for
-yourself, 
+yourself,
 the gccgo source code is accessible via Subversion. The
 GCC web site
 has <a href="https://gcc.gnu.org/svn.html">instructions for getting the

doc/go_faq.html

@@ -39,7 +39,7 @@ <h3 id="What_is_the_purpose_of_the_project">
 
 <p>
 These considerations led to
-<a href="https://commandcenter.blogspot.com/2017/09/go-ten-years-and-climbing.html">a 
+<a href="https://commandcenter.blogspot.com/2017/09/go-ten-years-and-climbing.html">a
 series of discussions</a> from which Go arose, first as a set of ideas and
 desiderata, then as a language.
 An overarching goal was that Go do more to help the working programmer
@@ -1282,7 +1282,7 @@ <h3 id="git_https">
 
 <p>
 Companies often permit outgoing traffic only on the standard TCP ports 80 (HTTP)
-and 443 (HTTPS), blocking outgoing traffic on other ports, including TCP port 9418 
+and 443 (HTTPS), blocking outgoing traffic on other ports, including TCP port 9418
 (git) and TCP port 22 (SSH).
 When using HTTPS instead of HTTP, <code>git</code> enforces certificate validation by
 default, providing protection against man-in-the-middle, eavesdropping and tampering attacks.

misc/trace/trace_viewer_full.html

@@ -397,23 +397,23 @@
     <span id="content"></span>
 
     <span id="significance">
-      
+
       <svg id="insignificant" viewBox="0 0 128 128">
         <circle cx="64" cy="64" r="60"></circle>
         <circle cx="44" cy="44" r="4"></circle>
         <circle cx="84" cy="44" r="4"></circle>
         <line x1="36" x2="92" y1="80" y2="80"></line>
       </svg>
 
-      
+
       <svg id="significantly_better" viewBox="0 0 128 128">
         <circle cx="64" cy="64" r="60"></circle>
         <circle cx="44" cy="44" r="4"></circle>
         <circle cx="84" cy="44" r="4"></circle>
         <path d="M 28 64 Q 64 128 100 64"></path>
       </svg>
 
-      
+
       <svg id="significantly_worse" viewBox="0 0 128 128">
         <circle cx="64" cy="64" r="60"></circle>
         <circle cx="44" cy="44" r="4"></circle>
@@ -677,7 +677,7 @@
 
   <div id="header"></div>
   <input id="stacking-distance-slider" max="400" min="1" step="1" type="range"/>
-  
+
   <canvas id="canvas"></canvas>
   <img id="chrome-left"/>
   <img id="chrome-mid"/>
@@ -815,7 +815,7 @@
     <label id="label"></label>
   </template>
 </dom-module><template id="chart-base-template">
-  <svg> 
+  <svg>
     <g id="chart-area" xmlns="http://www.w3.org/2000/svg">
       <g class="x axis"></g>
       <g class="y axis"></g>
@@ -1185,7 +1185,7 @@ <h1 id="blink_rcs_heading"></h1>
       <div id="label">Heap details</div>
       <div id="view_mode_container">
         <span>View mode:</span>
-        
+
       </div>
     </div>
     <div id="contents">
@@ -1392,11 +1392,11 @@ <h1 id="blink_rcs_heading"></h1>
         font-size: 15px;
       }
     </style>
-    
+
     <div id="label"></div>
     <div id="aggregation_mode_container">
       <span>Metric aggregation:</span>
-      
+
     </div>
   </template>
 </dom-module><dom-module id="tr-ui-a-stacked-pane-view">
@@ -1450,7 +1450,7 @@ <h1 id="blink_rcs_heading"></h1>
     </style>
     <tr-ui-b-table id="table">
     </tr-ui-b-table>
-    
+
   </template>
 </dom-module><dom-module id="tr-ui-a-selection-summary-table">
   <template>
@@ -1466,7 +1466,7 @@ <h1 id="blink_rcs_heading"></h1>
     </style>
     <tr-ui-b-table id="table">
     </tr-ui-b-table>
-    
+
   </template>
 </dom-module><dom-module id="tr-ui-b-radio-picker">
   <template>