Remove legacy StartsWithASCII function.

content/browser/renderer_host/render_widget_host_view_mac.mm

 // Copyright (c) 2012 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.
 
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
 
 #import <objc/runtime.h>
 #include <OpenGL/gl.h>
 #include <QuartzCore/QuartzCore.h>
 
@@ skipping 2973 matching lines @@
           CommandNameForSelector(selector) UTF8String]);
 
   // If this method is called when handling a key down event, then we need to
   // handle the command in the key event handler. Otherwise we can just handle
   // it here.
   if (handlingKeyDown_) {
     hasEditCommands_ = YES;
     // We ignore commands that insert characters, because this was causing
     // strange behavior (e.g. tab always inserted a tab rather than moving to
     // the next field on the page).
-    if (!base::StartsWithASCII(command, "insert", false))
+    if (!base::StartsWith(command, "insert",
+                          base::CompareCase::INSENSITIVE_ASCII))
       editCommands_.push_back(EditCommand(command, ""));
   } else {
     RenderWidgetHostImpl* rwh = renderWidgetHostView_->render_widget_host_;
     rwh->Send(new InputMsg_ExecuteEditCommand(rwh->GetRoutingID(),
                                               command, ""));
   }
 }
 
 - (void)insertText:(id)string replacementRange:(NSRange)replacementRange {
   // An input method has characters to be inserted.
@@ skipping 299 matching lines @@
 
 // "-webkit-app-region: drag | no-drag" is implemented on Mac by excluding
 // regions that are not draggable. (See ControlRegionView in
 // native_app_window_cocoa.mm). This requires the render host view to be
 // draggable by default.
 - (BOOL)mouseDownCanMoveWindow {
   return YES;
 }
 
 @end