Allow GraphicsContext3D to be created with a NULL WebView for offscreen

webkit/gpu/webgraphicscontext3d_in_process_impl.cc

Index: webkit/gpu/webgraphicscontext3d_in_process_impl.cc
===================================================================
--- webkit/gpu/webgraphicscontext3d_in_process_impl.cc	(revision 96767)
+++ webkit/gpu/webgraphicscontext3d_in_process_impl.cc	(working copy)
@@ -114,7 +114,8 @@
 
   if (!render_directly_to_web_view) {
     // Pick up the compositor's context to share resources with.
-    WebGraphicsContext3D* view_context = webView->graphicsContext3D();
+    WebGraphicsContext3D* view_context = webView ?
+                                         webView->graphicsContext3D() : NULL;
     if (view_context) {
       WebGraphicsContext3DInProcessImpl* contextImpl =
           static_cast<WebGraphicsContext3DInProcessImpl*>(view_context);
@@ -148,7 +149,7 @@
     // a page unload event, iterate down any live WebGraphicsContext3D instances
     // and force them to drop their contexts, sending a context lost event if
     // necessary.
-    webView->mainFrame()->collectGarbage();
+    if (webView) webView->mainFrame()->collectGarbage();
 
     gl_surface_ = gfx::GLSurface::CreateOffscreenGLSurface(false,
                                                            gfx::Size(1, 1));
@@ -169,7 +170,7 @@
     // a page unload event, iterate down any live WebGraphicsContext3D instances
     // and force them to drop their contexts, sending a context lost event if
     // necessary.
-    webView->mainFrame()->collectGarbage();
+    if (webView) webView->mainFrame()->collectGarbage();
 
     gl_context_ = gfx::GLContext::CreateGLContext(share_group,
                                                   gl_surface_.get());
@@ -1329,10 +1330,6 @@
     WGC3Denum target, WGC3Dint level, WGC3Denum internalFormat,
     WGC3Dsizei width, WGC3Dsizei height, WGC3Dint border,
     WGC3Denum format, WGC3Denum type, const void* pixels) {
-  if (width && height && !pixels) {
-    synthesizeGLError(GL_INVALID_VALUE);
-    return;
-  }
   makeContextCurrent();
   glTexImage2D(target, level, internalFormat,
                width, height, border, format, type, pixels);