views::Textfield: Implement transpose editing command.

ui/views/cocoa/bridged_content_view.mm

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ui/views/cocoa/bridged_content_view.h"
 
 #include "base/logging.h"
 #import "base/mac/mac_util.h"
 #import "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 959 matching lines @@
       ? [self moveToEndOfLineAndModifySelection:sender]
       : [self moveToBeginningOfLineAndModifySelection:sender];
 }
 
 - (void)moveToRightEndOfLineAndModifySelection:(id)sender {
   IsTextRTL(textInputClient_)
       ? [self moveToBeginningOfLineAndModifySelection:sender]
       : [self moveToEndOfLineAndModifySelection:sender];
 }
 
+// Graphical Element transposition
+
+- (void)transpose:(id)sender {
+  [self handleAction:ui::TextEditCommand::TRANSPOSE
+             keyCode:ui::VKEY_T
+             domCode:ui::DomCode::US_T

[karandeepb, 2016/06/28 03:26:27]

I am not sure if giving it the Ctrl+T keycode is appropriate here. I believe the
intention behind also providing Window/Linux specific key-codes in addition to
setting the command, is to take care of commands like PageUp, which are
currently handled using OnKeyPressed. But Ctrl+T on Windows/Linux doesn't mean
transpose. Maybe we should give a dummy keycode like ui::VKEY_UNKOWN?

+          eventFlags:ui::EF_CONTROL_DOWN];
+}
+
 // Deletions.
 
 - (void)deleteForward:(id)sender {
   [self handleAction:ui::TextEditCommand::DELETE_FORWARD
              keyCode:ui::VKEY_DELETE
              domCode:ui::DomCode::DEL
           eventFlags:0];
 }
 
 - (void)deleteBackward:(id)sender {
@@ skipping 256 matching lines @@
   }
 
   return [super accessibilityAttributeValue:attribute];
 }
 
 - (id)accessibilityHitTest:(NSPoint)point {
   return [hostedView_->GetNativeViewAccessible() accessibilityHitTest:point];
 }
 
 @end