Add support for transparent background API

apps/app_window.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 "apps/app_window.h"
 
 #include <algorithm>
 
 #include "apps/app_window_geometry_cache.h"
 #include "apps/app_window_registry.h"
@@ skipping 137 matching lines @@
 void AppWindow::BoundsSpecification::ResetBounds() {
   bounds.SetRect(kUnspecifiedPosition, kUnspecifiedPosition, 0, 0);
 }
 
 // AppWindow::CreateParams
 
 AppWindow::CreateParams::CreateParams()
     : window_type(AppWindow::WINDOW_TYPE_DEFAULT),
       frame(AppWindow::FRAME_CHROME),
       has_frame_color(false),
-      transparent_background(false),
+      alpha_enabled(false),
       creator_process_id(0),
       state(ui::SHOW_STATE_DEFAULT),
       hidden(false),
       resizable(true),
       focused(true),
-      always_on_top(false) {}
+      always_on_top(false) {
+}
 
 AppWindow::CreateParams::~CreateParams() {}
 
 gfx::Rect AppWindow::CreateParams::GetInitialWindowBounds(
     const gfx::Insets& frame_insets) const {
   // Combine into a single window bounds.
   gfx::Rect combined_bounds(window_spec.bounds);
   if (content_spec.bounds.x() != BoundsSpecification::kUnspecifiedPosition)
     combined_bounds.set_x(content_spec.bounds.x() - frame_insets.left());
   if (content_spec.bounds.y() != BoundsSpecification::kUnspecifiedPosition)
@@ skipping 56 matching lines @@
                      Delegate* delegate,
                      const extensions::Extension* extension)
     : browser_context_(context),
       extension_id_(extension->id()),
       window_type_(WINDOW_TYPE_DEFAULT),
       delegate_(delegate),
       image_loader_ptr_factory_(this),
       fullscreen_types_(FULLSCREEN_TYPE_NONE),
       show_on_first_paint_(false),
       first_paint_complete_(false),
-      cached_always_on_top_(false) {
+      cached_always_on_top_(false),
+      cached_alpha_enabled_(false) {
   extensions::ExtensionsBrowserClient* client =
       extensions::ExtensionsBrowserClient::Get();
   CHECK(!client->IsGuestSession(context) || context->IsOffTheRecord())
       << "Only off the record window may be opened in the guest mode.";
 }
 
 void AppWindow::Init(const GURL& url,
                      AppWindowContents* app_window_contents,
                      const CreateParams& params) {
   // Initialize the render interface and web contents
@@ skipping 18 matching lines @@
   // Initialize the window
   CreateParams new_params = LoadDefaults(params);
   window_type_ = new_params.window_type;
   window_key_ = new_params.window_key;
 
   // Windows cannot be always-on-top in fullscreen mode for security reasons.
   cached_always_on_top_ = new_params.always_on_top;
   if (new_params.state == ui::SHOW_STATE_FULLSCREEN)
     new_params.always_on_top = false;
 
+  cached_alpha_enabled_ = new_params.alpha_enabled;
+
   native_app_window_.reset(delegate_->CreateNativeAppWindow(this, new_params));
 
   if (new_params.hidden) {
     // Although the window starts hidden by default, calling Hide() here
     // notifies observers of the window being hidden.
     Hide();
   } else {
     // Panels are not activated by default.
     Show(window_type_is_panel() || !new_params.focused ? SHOW_INACTIVE
                                                        : SHOW_ACTIVE);
@@ skipping 429 matching lines @@
   // overlap the taskbar to be on top. The property will be applied when the
   // window exits fullscreen and moves away from the taskbar.
   if (!IsFullscreen(fullscreen_types_) && !IntersectsWithTaskbar())
     native_app_window_->SetAlwaysOnTop(always_on_top);
 
   OnNativeWindowChanged();
 }
 
 bool AppWindow::IsAlwaysOnTop() const { return cached_always_on_top_; }
 
+bool AppWindow::AlphaEnabled() const {
+  return cached_alpha_enabled_;
+}
+
 void AppWindow::GetSerializedState(base::DictionaryValue* properties) const {
   DCHECK(properties);
 
   properties->SetBoolean("fullscreen",
                          native_app_window_->IsFullscreenOrPending());
   properties->SetBoolean("minimized", native_app_window_->IsMinimized());
   properties->SetBoolean("maximized", native_app_window_->IsMaximized());
   properties->SetBoolean("alwaysOnTop", IsAlwaysOnTop());
+  properties->SetBoolean("alphaEnabled", AlphaEnabled());
   properties->SetBoolean("hasFrameColor", native_app_window_->HasFrameColor());
 
   // These properties are undocumented and are to enable testing. Alpha is
   // removed to
   // make the values easier to check.
   SkColor transparent_white = ~SK_ColorBLACK;
   properties->SetInteger(
       "activeFrameColor",
       native_app_window_->ActiveFrameColor() & transparent_white);
   properties->SetInteger(
@@ skipping 370 matching lines @@
         region.bounds.x(),
         region.bounds.y(),
         region.bounds.right(),
         region.bounds.bottom(),
         region.draggable ? SkRegion::kUnion_Op : SkRegion::kDifference_Op);
   }
   return sk_region;
 }
 
 }  // namespace apps