[blink] Support (semi-)transparent background colors in WebView/Frame.

content/renderer/render_view_impl.cc

 // 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/renderer/render_view_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <memory>
 
@@ skipping 146 matching lines @@
 #include "third_party/WebKit/public/web/WebRuntimeFeatures.h"
 #include "third_party/WebKit/public/web/WebScriptSource.h"
 #include "third_party/WebKit/public/web/WebSearchableFormData.h"
 #include "third_party/WebKit/public/web/WebSecurityPolicy.h"
 #include "third_party/WebKit/public/web/WebSettings.h"
 #include "third_party/WebKit/public/web/WebUserGestureIndicator.h"
 #include "third_party/WebKit/public/web/WebView.h"
 #include "third_party/WebKit/public/web/WebWindowFeatures.h"
 #include "third_party/icu/source/common/unicode/uchar.h"
 #include "third_party/icu/source/common/unicode/uscript.h"
+#include "third_party/skia/include/core/SkColor.h"
 #include "ui/base/ui_base_switches_util.h"
 #include "ui/events/latency_info.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/geometry/size_conversions.h"
 #include "ui/gfx/native_widget_types.h"
 #include "url/origin.h"
 #include "url/url_constants.h"
 #include "v8/include/v8.h"
@@ skipping 2058 matching lines @@
       params.browser_controls_shrink_blink_size;
   top_controls_height_ = params.top_controls_height;
 
   RenderWidget::OnResize(params);
 
   if (old_visible_viewport_size != visible_viewport_size_)
     has_scrolled_focused_editable_node_into_rect_ = false;
 }
 
 void RenderViewImpl::OnSetBackgroundOpaque(bool opaque) {
-  if (frame_widget_)
-    frame_widget_->setIsTransparent(!opaque);
-  if (compositor_)
-    compositor_->setHasTransparentBackground(!opaque);
+  if (!frame_widget_)
+    return;
+
+  if (opaque) {
+    frame_widget_->clearBaseBackgroundColorOverride();
+    frame_widget_->clearBackgroundColorOverride();
+  } else {
+    frame_widget_->setBaseBackgroundColorOverride(SK_ColorTRANSPARENT);
+    frame_widget_->setBackgroundColorOverride(SK_ColorTRANSPARENT);
+  }
 }
 
 void RenderViewImpl::OnSetActive(bool active) {
   if (webview())
     webview()->setIsActive(active);
 }
 
 blink::WebWidget* RenderViewImpl::GetWebWidget() const {
   if (frame_widget_)
     return frame_widget_;
@@ skipping 453 matching lines @@
                             INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
   }
 
   std::unique_ptr<InputEventAck> ack(
       new InputEventAck(InputEventAckSource::MAIN_THREAD, input_event->type(),
                         INPUT_EVENT_ACK_STATE_NOT_CONSUMED));
   OnInputEventAck(std::move(ack));
 }
 
 }  // namespace content