Add scroll and gesture message filters for UIPI Flash.

chrome/browser/renderer_host/render_widget_host_view_win.cc

Index: chrome/browser/renderer_host/render_widget_host_view_win.cc
===================================================================
--- chrome/browser/renderer_host/render_widget_host_view_win.cc	(revision 96590)
+++ chrome/browser/renderer_host/render_widget_host_view_win.cc	(working copy)
@@ -446,12 +446,33 @@
   }
   DCHECK(window_class);
 
+  HWND orig_parent = ::GetParent(window);
   HWND parent = CreateWindowEx(
       WS_EX_LEFT | WS_EX_LTRREADING | WS_EX_RIGHTSCROLLBAR,
       MAKEINTATOM(window_class), 0,
       WS_CHILD | WS_CLIPCHILDREN | WS_CLIPSIBLINGS,
-      0, 0, 0, 0, ::GetParent(window), 0, GetModuleHandle(NULL), 0);
+      0, 0, 0, 0, orig_parent, 0, GetModuleHandle(NULL), 0);
   ui::CheckWindowCreated(parent);
+  // If UIPI is enabled we need to add message filters for parents with
+  // children that cross process boundaries.
+  if (::GetPropW(orig_parent, webkit::npapi::kNativeWindowClassFilterProp)) {
+    // Process-wide message filters required on Vista must be added to:
+    // chrome_content_client.cc ChromeContentClient::SandboxPlugin
+    typedef BOOL (WINAPI *ChangeWindowMessageFilterExFunction)(
+        HWND hwnd,
+        UINT message,
+        DWORD action,
+        PCHANGEFILTERSTRUCT change_filter_struct);
+    static ChangeWindowMessageFilterExFunction s_ChangeWindowMessageFilterEx =

[M-A Ruel, 2011/08/12 23:50:05]

Say No! to local static variables! In incurs a global variable look up at each
first access in the function everytime the function is called.

Actually, why are you making it static if it is to set its value at each
function call?

+        reinterpret_cast<ChangeWindowMessageFilterExFunction>(
+            ::GetProcAddress(::GetModuleHandle(L"user32.dll"),
+                             "ChangeWindowMessageFilterEx"));
+    // Process-wide message filters required on Vista must be added to:
+    // chrome_content_client.cc ChromeContentClient::SandboxPlugin
+    s_ChangeWindowMessageFilterEx(parent, WM_MOUSEWHEEL, MSGFLT_ALLOW, NULL);
+    s_ChangeWindowMessageFilterEx(parent, WM_GESTURE, MSGFLT_ALLOW, NULL);
+    ::SetPropW(orig_parent, webkit::npapi::kNativeWindowClassFilterProp, NULL);
+  }
   ::SetParent(window, parent);
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,