Plugin Power Saver: Throttle 'large' plugins that appear small.

chrome/renderer/plugins/plugin_preroller.cc

 // Copyright 2015 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 "chrome/renderer/plugins/plugin_preroller.h"
 
 #include "base/base64.h"
 #include "chrome/grit/renderer_resources.h"
 #include "chrome/renderer/plugins/chrome_plugin_placeholder.h"
 #include "third_party/WebKit/public/platform/WebRect.h"
@@ skipping 10 matching lines @@
                                  const base::string16& name,
                                  const base::string16& message,
                                  content::PluginInstanceThrottler* throttler)
     : RenderFrameObserver(render_frame),
       frame_(frame),
       params_(params),
       info_(info),
       identifier_(identifier),
       name_(name),
       message_(message),
-      throttler_(throttler) {
+      throttler_(throttler),
+      keyframe_width_(0),
+      keyframe_height_(0) {
   DCHECK(throttler);
   throttler_->AddObserver(this);
 }
 
 PluginPreroller::~PluginPreroller() {
   if (throttler_)
     throttler_->RemoveObserver(this);
 }
 
 void PluginPreroller::OnKeyframeExtracted(const SkBitmap* bitmap) {
   std::vector<unsigned char> png_data;
   if (!gfx::PNGCodec::EncodeBGRASkBitmap(*bitmap, false, &png_data)) {
     DLOG(ERROR) << "Provided keyframe could not be encoded as PNG.";
     return;
   }
 
   base::StringPiece png_as_string(reinterpret_cast<char*>(&png_data[0]),
                                   png_data.size());
 
   std::string data_url_header = "data:image/png;base64,";
   std::string data_url_body;
   base::Base64Encode(png_as_string, &data_url_body);
   keyframe_data_url_ = GURL(data_url_header + data_url_body);
+  keyframe_width_ = bitmap->width();

[Lei Zhang, 2015/03/18 00:19:32]

This is gfx::Size::SetToMin(), right?

[tommycli, 2015/03/18 00:39:33]

Done.

+  keyframe_height_ = bitmap->height();
 }
 
 void PluginPreroller::OnThrottleStateChange() {
   if (!throttler_->IsThrottled())
     return;
 
+  int width = std::min(keyframe_width_, throttler_->GetWidth());

[Lei Zhang, 2015/03/18 00:19:32]

This is gfx::Size::SetToMin() right?

[tommycli, 2015/03/18 00:39:33]

Done.

+  int height = std::min(keyframe_height_, throttler_->GetHeight());
+
   ChromePluginPlaceholder* placeholder =
       ChromePluginPlaceholder::CreateBlockedPlugin(
           render_frame(), frame_, params_, info_, identifier_, name_,
-          IDR_PLUGIN_POSTER_HTML, message_, keyframe_data_url_.spec(), GURL());
+          IDR_PLUGIN_POSTER_HTML, message_, keyframe_data_url_.spec(), GURL(),
+          width, height);
   placeholder->SetPremadePlugin(throttler_);
   placeholder->set_power_saver_enabled(true);
   placeholder->set_allow_loading(true);
 
   blink::WebPluginContainer* container =
       throttler_->GetWebPlugin()->container();
   container->setPlugin(placeholder->plugin());
 
   bool success = placeholder->plugin()->initialize(container);
   DCHECK(success);
 
   container->invalidate();
   container->reportGeometry();
 
   delete this;
 }
 
 void PluginPreroller::OnThrottlerDestroyed() {
   throttler_ = nullptr;
   delete this;
 }