[devtools] Remove device emulation background color override.

third_party/WebKit/Source/web/DevToolsEmulator.cpp

Index: third_party/WebKit/Source/web/DevToolsEmulator.cpp
diff --git a/third_party/WebKit/Source/web/DevToolsEmulator.cpp b/third_party/WebKit/Source/web/DevToolsEmulator.cpp
index 7f771b55bca0c3916221ffa036c4cdbd7c12081b..4b82e5a90ba40a4b65c75fb851faa16138948f8f 100644
--- a/third_party/WebKit/Source/web/DevToolsEmulator.cpp
+++ b/third_party/WebKit/Source/web/DevToolsEmulator.cpp
@@ -223,12 +223,7 @@ void DevToolsEmulator::EnableDeviceEmulation(
     GetMemoryCache()->EvictResources();
 
   emulation_params_ = params;
-
-  if (!device_metrics_enabled_) {
-    device_metrics_enabled_ = true;
-    if (params.view_size.width || params.view_size.height)
-      web_view_impl_->SetBackgroundColorOverride(Color::kDarkGray);

[dgozman, 2017/04/12 18:21:23]

Remove these methods from WebViewImpl as well?

[Eric Seckler, 2017/04/12 19:31:31]

After my recent refactorings of transparency overrides, these methods are now
actually used for a non-devtools purpose, too:
https://cs.chromium.org/chromium/src/content/renderer/render_view_impl.cc?l=2240

-  }
+  device_metrics_enabled_ = true;
 
   web_view_impl_->GetPage()->GetSettings().SetDeviceScaleAdjustment(
       calculateDeviceScaleAdjustment(params.view_size.width,
@@ -258,7 +253,6 @@ void DevToolsEmulator::DisableDeviceEmulation() {
 
   GetMemoryCache()->EvictResources();
   device_metrics_enabled_ = false;
-  web_view_impl_->ClearBackgroundColorOverride();
   web_view_impl_->GetPage()->GetSettings().SetDeviceScaleAdjustment(
       embedder_device_scale_adjustment_);
   DisableMobileEmulation();