aw: Add command switch to disable hardware acceleration

android_webview/browser/browser_view_renderer.cc

 // 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.
 
 #include "android_webview/browser/browser_view_renderer.h"
 
 #include "android_webview/browser/browser_view_renderer_client.h"
 #include "android_webview/browser/shared_renderer_state.h"
+#include "android_webview/common/aw_switches.h"
 #include "android_webview/public/browser/draw_gl.h"
 #include "base/android/jni_android.h"
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/json/json_writer.h"
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "cc/output/compositor_frame.h"
@@ skipping 198 matching lines @@
                                  bool is_hardware_canvas,
                                  const gfx::Vector2d& scroll,
                                  const gfx::Rect& global_visible_rect,
                                  const gfx::Rect& clip) {
   last_on_draw_scroll_offset_ = scroll;
   last_on_draw_global_visible_rect_ = global_visible_rect;
 
   if (clear_view_)
     return false;
 
-  if (is_hardware_canvas && attached_to_window_)
+  if (is_hardware_canvas && attached_to_window_ &&
+      !switches::ForceAuxiliaryBitmap()) {
     return OnDrawHardware(java_canvas);
+  }
+
   // Perform a software draw
   return DrawSWInternal(java_canvas, clip);
 }
 
 bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
   if (!compositor_)
     return false;
 
   if (!hardware_enabled_) {
     hardware_enabled_ = compositor_->InitializeHwDraw();
@@ skipping 514 matching lines @@
     base::StringAppendF(&str,
                         "surface width height: [%d %d] ",
                         draw_info->width,
                         draw_info->height);
     base::StringAppendF(&str, "is_layer: %d ", draw_info->is_layer);
   }
   return str;
 }
 
 }  // namespace android_webview