Releasing CPU resources of hidden/minimized browser windows

BUG=310365
TEST=browser_test & tested visually (taskamanger, running YouTube, deleting active&inactive hidden tabs, ..)

Review URL: https://codereview.chromium.org/286943005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@272662 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/web_contents/web_contents_impl.h

@@ -164,6 +164,8 @@ class CONTENT_EXPORT WebContentsImpl
     return geolocation_dispatcher_host_.get();
   }
 
+  bool should_normally_be_visible() { return should_normally_be_visible_; }
+
   // WebContents ------------------------------------------------------
   virtual WebContentsDelegate* GetDelegate() OVERRIDE;
   virtual void SetDelegate(WebContentsDelegate* delegate) OVERRIDE;

content/browser/web_contents/web_contents_view_aura.cc

@@ -98,6 +98,17 @@ bool ShouldNavigateBack(const NavigationController& controller,
          controller.CanGoBack();
 }
 
+// Update the |web contents| to be |visible|.
+void UpdateWebContentsVisibility(WebContentsImpl* web_contents, bool visible) {
+  if (visible) {
+    if (!web_contents->should_normally_be_visible())
+      web_contents->WasShown();
+  } else {
+    if (web_contents->should_normally_be_visible())
+      web_contents->WasHidden();
+  }
+}
+
 RenderWidgetHostViewAura* ToRenderWidgetHostViewAura(
     RenderWidgetHostView* view) {
   if (!view || RenderViewHostFactory::has_factory())
@@ -717,6 +728,7 @@ WebContentsViewAura::~WebContentsViewAura() {
     return;
 
   window_observer_.reset();
+  window_->RemoveObserver(this);
 
   // Window needs a valid delegate during its destructor, so we explicitly
   // delete it here.
@@ -1044,6 +1056,7 @@ void WebContentsViewAura::CreateView(
   window_->SetType(ui::wm::WINDOW_TYPE_CONTROL);
   window_->SetTransparent(false);
   window_->Init(aura::WINDOW_LAYER_NOT_DRAWN);
+  window_->AddObserver(this);
   aura::Window* root_window = context ? context->GetRootWindow() : NULL;
   if (root_window) {
     // There are places where there is no context currently because object
@@ -1426,10 +1439,6 @@ void WebContentsViewAura::OnWindowDestroyed(aura::Window* window) {
 }
 
 void WebContentsViewAura::OnWindowTargetVisibilityChanged(bool visible) {
-  if (visible)
-    web_contents_->WasShown();
-  else
-    web_contents_->WasHidden();
 }
 
 bool WebContentsViewAura::HasHitTestMask() const {
@@ -1552,4 +1561,22 @@ int WebContentsViewAura::OnPerformDrop(const ui::DropTargetEvent& event) {
   return ConvertFromWeb(current_drag_op_);
 }
 
+void WebContentsViewAura::OnWindowParentChanged(aura::Window* window,
+                                                aura::Window* parent) {
+  // On Windows we will get called with a parent of NULL as part of the shut
+  // down process. As such we do only change the visibility when a parent gets
+  // set.
+  if (parent)
+    UpdateWebContentsVisibility(web_contents_, window->IsVisible());
+}
+
+void WebContentsViewAura::OnWindowVisibilityChanged(aura::Window* window,
+                                                    bool visible) {
+  // Ignore any visibility changes in the hierarchy below.
+  if (window != window_.get() && window_->Contains(window))
+    return;
+
+  UpdateWebContentsVisibility(web_contents_, visible);
+}
+
 }  // namespace content

content/browser/web_contents/web_contents_view_aura.h

@@ -14,6 +14,7 @@
 #include "content/browser/web_contents/web_contents_view.h"
 #include "content/common/content_export.h"
 #include "ui/aura/window_delegate.h"
+#include "ui/aura/window_observer.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/wm/public/drag_drop_delegate.h"
 
@@ -41,7 +42,8 @@ class WebContentsViewAura
       public OverscrollControllerDelegate,
       public ui::ImplicitAnimationObserver,
       public aura::WindowDelegate,
-      public aura::client::DragDropDelegate {
+      public aura::client::DragDropDelegate,
+      public aura::WindowObserver {
  public:
   WebContentsViewAura(WebContentsImpl* web_contents,
                       WebContentsViewDelegate* delegate);
@@ -176,6 +178,12 @@ class WebContentsViewAura
   virtual void OnDragExited() OVERRIDE;
   virtual int OnPerformDrop(const ui::DropTargetEvent& event) OVERRIDE;
 
+  // Overridden from aura::WindowObserver:
+  virtual void OnWindowParentChanged(aura::Window* window,
+                                     aura::Window* parent) OVERRIDE;
+  virtual void OnWindowVisibilityChanged(aura::Window* window,
+                                         bool visible) OVERRIDE;
+
   scoped_ptr<aura::Window> window_;
 
   // The window that shows the screenshot of the history page during an

content/browser/web_contents/web_contents_view_aura_browsertest.cc

@@ -587,8 +587,7 @@ IN_PROC_BROWSER_TEST_F(WebContentsViewAuraTest,
   window->AddChild(shell()->web_contents()->GetContentNativeView());
 }
 
-IN_PROC_BROWSER_TEST_F(WebContentsViewAuraTest,
-                       ContentWindowClose) {
+IN_PROC_BROWSER_TEST_F(WebContentsViewAuraTest, ContentWindowClose) {
   ASSERT_NO_FATAL_FAILURE(
       StartTestWithPage("files/overscroll_navigation.html"));
 
@@ -677,4 +676,18 @@ IN_PROC_BROWSER_TEST_F(WebContentsViewAuraTest,
   EXPECT_FALSE(controller.CanGoForward());
 }
 
+// Verify that hiding a parent of the renderer will hide the content too.
+IN_PROC_BROWSER_TEST_F(WebContentsViewAuraTest, HideContentOnParenHide) {
+  ASSERT_NO_FATAL_FAILURE(StartTestWithPage("files/title1.html"));
+  WebContentsImpl* web_contents =
+      static_cast<WebContentsImpl*>(shell()->web_contents());
+  aura::Window* content = web_contents->GetNativeView()->parent();
+  aura::Window* parent = content->parent();
+  EXPECT_TRUE(web_contents->should_normally_be_visible());
+  parent->Hide();
+  EXPECT_FALSE(web_contents->should_normally_be_visible());
+  parent->Show();
+  EXPECT_TRUE(web_contents->should_normally_be_visible());
+}
+
 }  // namespace content