Allow creating WinCompositorWidgetProxy without an nsWindow. (bug 1281998 part 1, r=jimm)

widget/windows/WinCompositorWidgetProxy.cpp

@@ -13,17 +13,18 @@ namespace widget {
 
 using namespace mozilla::gfx;
 
-WinCompositorWidgetProxy::WinCompositorWidgetProxy(nsWindow* aWindow)
+WinCompositorWidgetProxy::WinCompositorWidgetProxy(HWND aWnd,
+                                                   uintptr_t aWidgetKey,
+                                                   nsTransparencyMode aMode,
+                                                   nsWindow* aWindow)
  : mWindow(aWindow),
-   mWidgetKey(reinterpret_cast<uintptr_t>(aWindow)),
-   mWnd(reinterpret_cast<HWND>(aWindow->GetNativeData(NS_NATIVE_WINDOW))),
-   mTransparencyMode(aWindow->GetTransparencyMode()),
+   mWidgetKey(aWidgetKey),
+   mWnd(aWnd),
+   mTransparencyMode(aMode),
    mMemoryDC(nullptr),
    mCompositeDC(nullptr),
    mLockedBackBufferData(nullptr)
 {
-  MOZ_ASSERT(aWindow);
-  MOZ_ASSERT(!aWindow->Destroyed());
   MOZ_ASSERT(mWnd && ::IsWindow(mWnd));
 }
 
@@ -54,6 +55,7 @@ WinCompositorWidgetProxy::PostRender(layers::LayerManagerComposite* aManager)
 nsIWidget*
 WinCompositorWidgetProxy::RealWidget()
 {
+  MOZ_ASSERT(mWindow);
   return mWindow;
 }
 

widget/windows/WinCompositorWidgetProxy.h

@@ -21,7 +21,10 @@ namespace widget {
 class WinCompositorWidgetProxy : public CompositorWidgetProxy
 {
 public:
-  WinCompositorWidgetProxy(nsWindow* aWindow);
+  WinCompositorWidgetProxy(HWND aWnd,
+                           uintptr_t aWidgetKey,
+                           nsTransparencyMode aMode,
+                           nsWindow* aWindow = nullptr);
 
   bool PreRender(layers::LayerManagerComposite*) override;
   void PostRender(layers::LayerManagerComposite*) override;

widget/windows/nsWindow.cpp

@@ -3621,7 +3621,7 @@ nsWindow::GetLayerManager(PLayerTransactionChild* aShadowManager,
     // Ensure we have a widget proxy even if we're not using the compositor,
     // since that's where we handle transparent windows.
     if (!mCompositorWidgetProxy) {
-      mCompositorWidgetProxy = new WinCompositorWidgetProxy(this);
+      mCompositorWidgetProxy = NewCompositorWidgetProxy();
     }
 
     mLayerManager = CreateBasicLayerManager();
@@ -3687,7 +3687,11 @@ nsWindow::OnDefaultButtonLoaded(const LayoutDeviceIntRect& aButtonRect)
 mozilla::widget::CompositorWidgetProxy*
 nsWindow::NewCompositorWidgetProxy()
 {
-  return new WinCompositorWidgetProxy(this);
+  return new WinCompositorWidgetProxy(
+    mWnd,
+    reinterpret_cast<uintptr_t>(this),
+    mTransparencyMode,
+    this);
 }
 
 mozilla::widget::WinCompositorWidgetProxy*