[EditCommandSource] Pass source through |CompositeEditCommand| ctor instead of |apply(source)|

third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h

Index: third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
diff --git a/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h b/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
index f6c2930ffa5ed34bbca22557c192a8fac3e8c561..bbb6d5a3a98f528012cb3deec22ff264cfcecfb1 100644
--- a/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
+++ b/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
@@ -42,7 +42,11 @@ class HTMLElement;
 class HTMLSpanElement;
 class Text;
 
-enum class EditCommandSource { kMenuOrKeyBinding, kDOM };
+enum class EditCommandSource {
+  kMenuOrKeyBinding,  // from menu, or keyboard shortcut

[yosin_UTC9, 2017/01/12 04:01:13]

I prefer to use |kUserAction| instead of |kMenuOrKeyBinding|. Because
|kMenuOrKeyBinding| is too specific of user action, in the future, we may
support user gesture, voice, eye tracking, brain reading etc.

[chongz, 2017/01/13 16:28:27]

Will do.

+  kDOM,               // document.execCommand()

[yosin_UTC9, 2017/01/12 04:01:13]

I prefer to use |kExecCommand|, |kScriptAPI|, or another indicating the command
created as result of |document.execCommand()|.

[chongz, 2017/01/13 16:28:27]

Will do.

+  kInternal,          // Blink creates a command for implementation.
+};
 
 class EditCommandComposition final : public UndoStep {
  public:
@@ -100,7 +104,7 @@ class CORE_EXPORT CompositeEditCommand : public EditCommand {
   ~CompositeEditCommand() override;
 
   // Returns |false| if the command failed.  e.g. It's aborted.
-  bool apply(EditCommandSource);
+  bool apply();
   bool isFirstCommand(EditCommand* command) {
     return !m_commands.isEmpty() && m_commands.front() == command;
   }
@@ -120,7 +124,9 @@ class CORE_EXPORT CompositeEditCommand : public EditCommand {
   DECLARE_VIRTUAL_TRACE();
 
  protected:
-  explicit CompositeEditCommand(Document&);
+  explicit CompositeEditCommand(
+      Document&,
+      EditCommandSource = EditCommandSource::kInternal);
 
   // TODO(chongz): Implement "beforeinput" as described below:
   // Fires "beforeinput" and will return |false| to cancel applying editing if
@@ -281,6 +287,7 @@ class CORE_EXPORT CompositeEditCommand : public EditCommand {
   bool isCompositeEditCommand() const final { return true; }
 
   Member<EditCommandComposition> m_composition;
+  EditCommandSource m_source;
 };
 
 DEFINE_TYPE_CASTS(CompositeEditCommand,