Refactor cc scrollbar layers to separate solid-color vs desktop.

content/renderer/gpu/render_widget_compositor.cc

Index: content/renderer/gpu/render_widget_compositor.cc
diff --git a/content/renderer/gpu/render_widget_compositor.cc b/content/renderer/gpu/render_widget_compositor.cc
index 9f9c5961258ef460d16dc05d8441de0a7fc8b9de..97d425f6b088ed41b4de169f9a0d3112d2af4998 100644
--- a/content/renderer/gpu/render_widget_compositor.cc
+++ b/content/renderer/gpu/render_widget_compositor.cc
@@ -74,6 +74,21 @@ bool GetSwitchValueAsFloat(
   }
 }
 
+bool StringToSkColor(const std::string& str, SkColor& color) {
+  std::string prefix = str.substr(0, 2);
+  int offset = (prefix == "0x" || prefix == "0X") ? 2 : 0;
+
+  std::vector<uint8> values;
+  if (base::HexStringToBytes(str.substr(offset), &values)) {
+    if (values.size() != 4)
+      return false;
+
+    color = SkColorSetARGB(values[0], values[1], values[2], values[3]);
+    return true;
+  }
+
+  return false;
+}
 
 }  // namespace
 
@@ -262,16 +277,20 @@ scoped_ptr<RenderWidgetCompositor> RenderWidgetCompositor::Create(
 
   settings.use_map_image = cmd->HasSwitch(cc::switches::kUseMapImage);
 
+  if (cmd->HasSwitch(cc::switches::kSolidColorScrollbarColor)) {
+    std::string str =
+        cmd->GetSwitchValueASCII(cc::switches::kSolidColorScrollbarColor);
+
+    SkColor scrollbar_color;
+    if (StringToSkColor(str, scrollbar_color))
+      settings.solid_color_scrollbar_color = scrollbar_color;
+  }
+
 #if defined(OS_ANDROID)
   // TODO(danakj): Move these to the android code.
   settings.can_use_lcd_text = false;
   settings.max_partial_texture_updates = 0;
-  settings.use_linear_fade_scrollbar_animator = true;
   settings.solid_color_scrollbars = true;
-  settings.solid_color_scrollbar_color =
-      cmd->HasSwitch(switches::kHideScrollbars)
-          ? SK_ColorTRANSPARENT
-          : SkColorSetARGB(128, 128, 128, 128);
   settings.highp_threshold_min = 2048;
   // Android WebView handles root layer flings itself.
   settings.ignore_root_layer_flings =
@@ -280,7 +299,6 @@ scoped_ptr<RenderWidgetCompositor> RenderWidgetCompositor::Create(
   if (cmd->HasSwitch(switches::kEnableOverlayScrollbars)) {
     settings.use_linear_fade_scrollbar_animator = true;
     settings.solid_color_scrollbars = true;
-    settings.solid_color_scrollbar_color = SkColorSetARGB(128, 128, 128, 128);
   }
 #endif