Removed "compositor" child window that was created by the GPU process.Removed the sync IPC that it used to ask the browser process to resize on Linux. Adapted windows to use the same mechanism.TEST=test webgl pages on windows (ANGLE and GL), linux and mac, run try job on windows, linux, mac. checkdeps failure look unrelated to patch.BUG=77536

Review URL: http://codereview.chromium.org/6880218

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@83248 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 19 insertions, 40 deletions

diff --git a/chrome/browser/renderer_host/render_widget_host_view_win.cc b/chrome/browser/renderer_host/render_widget_host_view_win.cc
index a889910..320880f 100644
--- a/chrome/browser/renderer_host/render_widget_host_view_win.cc
+++ b/chrome/browser/renderer_host/render_widget_host_view_win.cc
@@ -80,6 +80,10 @@ const int kMaxTooltipLength = 1024;
 // listening for MSAA events.
 const int kIdCustom = 1;
 
+// The delay before the compositor host window is destroyed. This gives the GPU
+// process a grace period to stop referencing it.
+const int kDestroyCompositorHostWindowDelay = 10000;
+
 const char* const kRenderWidgetHostViewKey = "__RENDER_WIDGET_HOST_VIEW__";
 
 // A callback function for EnumThreadWindows to enumerate and dismiss
@@ -319,11 +323,6 @@ void RenderWidgetHostViewWin::SetBounds(const gfx::Rect& rect) {
     ScreenToClient(&point);
 
   SetWindowPos(NULL, point.x, point.y, rect.width(), rect.height(), swp_flags);
-  if (compositor_host_window_) {
-    ::SetWindowPos(compositor_host_window_, NULL, point.x, point.y,
-        rect.width(), rect.height(),
-        SWP_NOSENDCHANGING | SWP_NOCOPYBITS | SWP_NOZORDER | SWP_NOACTIVATE);
-  }
   render_widget_host_->WasResized();
   EnsureTooltip();
 }
@@ -462,14 +461,20 @@ void RenderWidgetHostViewWin::CleanupCompositorWindow() {
   if (!compositor_host_window_)
     return;
 
-  std::vector<HWND> all_child_windows;
-  ::EnumChildWindows(compositor_host_window_, AddChildWindowToVector,
-    reinterpret_cast<LPARAM>(&all_child_windows));
-  if (all_child_windows.size()) {
-    DCHECK(all_child_windows.size() == 1);
-    ::ShowWindow(all_child_windows[0], SW_HIDE);
-    ::SetParent(all_child_windows[0], NULL);
-  }
+  // Hide the compositor and parent it to the desktop rather than destroying
+  // it immediately. The GPU process has a grace period to stop accessing the
+  // window. TODO(apatrick): the GPU process should acknowledge that it has
+  // finished with the window handle and the browser process should destroy it
+  // at that point.
+  ::ShowWindow(compositor_host_window_, SW_HIDE);
+  ::SetParent(compositor_host_window_, NULL);
+
+  BrowserThread::PostDelayedTask(
+      BrowserThread::UI,
+      FROM_HERE,
+      NewRunnableFunction(::DestroyWindow, compositor_host_window_),
+      kDestroyCompositorHostWindowDelay);
+
   compositor_host_window_ = NULL;
 }
 
@@ -1466,31 +1471,10 @@ void RenderWidgetHostViewWin::Observe(NotificationType type,
   browser_accessibility_manager_.reset(NULL);
 }
 
-// Looks through the children windows of the CompositorHostWindow. If the
-// compositor child window is found, its size is checked against the host
-// window's size. If the child is smaller in either dimensions, we fill
-// the host window with white to avoid unseemly cracks.
 static void PaintCompositorHostWindow(HWND hWnd) {
   PAINTSTRUCT paint;
   BeginPaint(hWnd, &paint);
 
-  std::vector<HWND> child_windows;
-  EnumChildWindows(hWnd, AddChildWindowToVector,
-      reinterpret_cast<LPARAM>(&child_windows));
-
-  if (child_windows.size()) {
-    HWND child = child_windows[0];
-
-    RECT host_rect, child_rect;
-    GetClientRect(hWnd, &host_rect);
-    if (GetClientRect(child, &child_rect)) {
-      if (child_rect.right < host_rect.right ||
-         child_rect.bottom != host_rect.bottom) {
-          FillRect(paint.hdc, &host_rect,
-              static_cast<HBRUSH>(GetStockObject(WHITE_BRUSH)));
-      }
-    }
-  }
   EndPaint(hWnd, &paint);
 }
 
@@ -1562,12 +1546,7 @@ void RenderWidgetHostViewWin::ShowCompositorHostWindow(bool show) {
     return;
 
   if (show) {
-    UINT flags = SWP_NOSENDCHANGING | SWP_NOCOPYBITS | SWP_NOZORDER |
-      SWP_NOACTIVATE | SWP_DEFERERASE | SWP_SHOWWINDOW;
-    gfx::Rect rect = GetViewBounds();
-    ::SetWindowPos(compositor_host_window_, NULL, 0, 0,
-        rect.width(), rect.height(),
-        flags);
+    ::ShowWindow(compositor_host_window_, SW_SHOW);
 
     // Get all the child windows of this view, including the compositor window.
     std::vector<HWND> all_child_windows;