From 54bd145ea8d6f197973a0c60d32bc42c86c91e53 Mon Sep 17 00:00:00 2001 From: "dglazkov@chromium.org" Date: Tue, 4 Aug 2009 16:49:00 +0000 Subject: Don't call NPP_SetWindow during the painting of windowless plugins. On Windows, Flash seems to only start executing script actions after it received an NPP_SetWindow with a non-NULL NPWindow.window (HDC). It is possible that Flash then invokes JS to modify DOM of the page. If Flash movie's widget is on-screen at page load, this call is made during layout and before even the NPP_Write is called, which is the desired sequence of events. However, if it is off-screen, this call occurs during painting, which leads to re-entrancy issues (layout while painting) and bizarre crashes. As a solution, we remove calls to NPP_SetWindow during painting and instead opt to never provide a null HDC to the plugin. If no valid HDC is available, we feed it a disposable monochrome 1x1 context to have at least something to draw on. R=ananta,darin,jam BUG=16114 TEST=LayoutTests/plugins/flash-setwindow-paint-crash.html (bug reduction). Review URL: http://codereview.chromium.org/159717 git-svn-id: svn://svn.chromium.org/chrome/trunk/src@22383 0039d316-1c4b-4281-b951-d872f2087c98 --- webkit/glue/plugins/webplugin_delegate_impl.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'webkit/glue/plugins/webplugin_delegate_impl.h') diff --git a/webkit/glue/plugins/webplugin_delegate_impl.h b/webkit/glue/plugins/webplugin_delegate_impl.h index 9fec1f6..408a710 100644 --- a/webkit/glue/plugins/webplugin_delegate_impl.h +++ b/webkit/glue/plugins/webplugin_delegate_impl.h @@ -162,6 +162,8 @@ class WebPluginDelegateImpl : public WebPluginDelegate { gfx::Rect windowed_last_pos_; #endif + // TODO(dglazkov): No longer used by Windows, make sure the removal + // causes no regressions and eliminate from other platforms. // this is an optimization to avoid calling SetWindow to the plugin // when it is not necessary. Initially, we need to call SetWindow, // and after that we only need to call it when the geometry changes. -- cgit v1.1