Introduce InsertIncrementalTextCommand to respect existing style for composition

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

Index: third_party/WebKit/Source/core/editing/commands/TypingCommand.h
diff --git a/third_party/WebKit/Source/core/editing/commands/TypingCommand.h b/third_party/WebKit/Source/core/editing/commands/TypingCommand.h
index a21fa5177dcd6d12499e2e05e337499d259e7812..e3d74e15ac2193d18b1a9b3e421bfd3c7cb3c222 100644
--- a/third_party/WebKit/Source/core/editing/commands/TypingCommand.h
+++ b/third_party/WebKit/Source/core/editing/commands/TypingCommand.h
@@ -69,7 +69,8 @@ class CORE_EXPORT TypingCommand final : public CompositeEditCommand {
   static void insertText(Document&,
                          const String&,
                          Options,
-                         TextCompositionType = TextCompositionNone);
+                         TextCompositionType = TextCompositionNone,
+                         bool isIncrementalInsertion = false);
   static void insertText(Document&,
                          const String&,
                          const VisibleSelection&,
@@ -156,8 +157,10 @@ class CORE_EXPORT TypingCommand final : public CompositeEditCommand {
     m_commandType = typingCommand;
   }
 
+  bool isIncrementalInsertion() const { return m_isIncrementalInsertion; }
+
   ETypingCommand m_commandType;
-  String m_textToInsert;
+  String m_text;
   bool m_openForMoreTyping;
   bool m_selectInsertedText;
   bool m_smartDelete;
@@ -173,6 +176,8 @@ class CORE_EXPORT TypingCommand final : public CompositeEditCommand {
 
   bool m_shouldRetainAutocorrectionIndicator;
   bool m_shouldPreventSpellChecking;
+
+  static bool m_isIncrementalInsertion;
 };
 
 DEFINE_TYPE_CASTS(TypingCommand,