Don't create child window for WGL.

ui/gl/gl_surface_wgl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/gl/gl_surface_wgl.h"
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/gl/gl_bindings.h"
@@ skipping 158 matching lines @@
   initialized = true;
   return true;
 }
 
 HDC GLSurfaceWGL::GetDisplayDC() {
   return g_display->device_context();
 }
 
 NativeViewGLSurfaceWGL::NativeViewGLSurfaceWGL(gfx::AcceleratedWidget window)
     : window_(window),
-      child_window_(NULL),
       device_context_(NULL) {
   DCHECK(window);
 }
 
 NativeViewGLSurfaceWGL::~NativeViewGLSurfaceWGL() {
   Destroy();
 }
 
 bool NativeViewGLSurfaceWGL::Initialize() {
   DCHECK(!device_context_);
 
-  RECT rect;
-  if (!GetClientRect(window_, &rect)) {
-    LOG(ERROR) << "GetClientRect failed.\n";
+  DWORD process_id;
+  GetWindowThreadProcessId(window_, &process_id);
+  if (process_id != GetCurrentProcessId()) {
+    LOG(ERROR) << "Can't use window created in " << process_id
+               << " with wgl in " << GetCurrentProcessId();
     Destroy();
     return false;
   }
 
-  // Create a child window. WGL has problems using a window handle owned by
-  // another process.
-  child_window_ = CreateWindow(
-      reinterpret_cast<wchar_t*>(g_display->window_class()),
-      L"",
-      WS_CHILDWINDOW | WS_DISABLED | WS_VISIBLE,
-      0, 0,
-      rect.right - rect.left,
-      rect.bottom - rect.top,
-      window_,
-      NULL,
-      NULL,
-      NULL);
-  if (!child_window_) {
-    LOG(ERROR) << "CreateWindow failed.\n";
-    Destroy();
-    return false;
-  }
-
-  // The GL context will render to this window.
-  device_context_ = GetDC(child_window_);
+  device_context_ = GetDC(window_);
   if (!device_context_) {
     LOG(ERROR) << "Unable to get device context for window.";
     Destroy();
     return false;
   }
 
   if (!SetPixelFormat(device_context_,
                       g_display->pixel_format(),
                       &kPixelFormatDescriptor)) {
     LOG(ERROR) << "Unable to set the pixel format for GL context.";
     Destroy();
     return false;
   }
 
   return true;
 }
 
 void NativeViewGLSurfaceWGL::Destroy() {
-  if (child_window_ && device_context_)
-    ReleaseDC(child_window_, device_context_);
+  if (window_ && device_context_)
+    ReleaseDC(window_, device_context_);
 
-  if (child_window_)
-    DestroyWindow(child_window_);
-
-  child_window_ = NULL;
   device_context_ = NULL;
 }
 
 bool NativeViewGLSurfaceWGL::IsOffscreen() {
   return false;
 }
 
 bool NativeViewGLSurfaceWGL::SwapBuffers() {
   TRACE_EVENT2("gpu", "NativeViewGLSurfaceWGL:RealSwapBuffers",
       "width", GetSize().width(),
       "height", GetSize().height());
 
-  // Resize the child window to match the parent before swapping. Do not repaint
-  // it as it moves.
-  RECT rect;
-  if (!GetClientRect(window_, &rect))
-    return false;
-  if (!MoveWindow(child_window_,
-                  0, 0,
-                  rect.right - rect.left,
-                  rect.bottom - rect.top,
-                  FALSE)) {
-    return false;
-  }
-
   DCHECK(device_context_);
   return ::SwapBuffers(device_context_) == TRUE;
 }
 
 gfx::Size NativeViewGLSurfaceWGL::GetSize() {
   RECT rect;
-  BOOL result = GetClientRect(child_window_, &rect);
+  BOOL result = GetClientRect(window_, &rect);
   DCHECK(result);
   return gfx::Size(rect.right - rect.left, rect.bottom - rect.top);
 }
 
 void* NativeViewGLSurfaceWGL::GetHandle() {
   return device_context_;
 }
 
 PbufferGLSurfaceWGL::PbufferGLSurfaceWGL(const gfx::Size& size)
     : size_(size),
@@ skipping 63 matching lines @@
 
 gfx::Size PbufferGLSurfaceWGL::GetSize() {
   return size_;
 }
 
 void* PbufferGLSurfaceWGL::GetHandle() {
   return device_context_;
 }
 
 }  // namespace gfx