Enable support for Offscreen rendering.

This patch enables support for Off-Screen rendering, which
is essential to support WebGL and other cases like Accelerated
Canvas2D. After this change, we should be able to run all web
pages using WebGL. We still have some conformance test failures,
which will be fixed in follow up patches.

Upstream CL: https://codereview.chromium.org/49533003/

patches/0004-Chromium-Add-gl-changes-for-Wayland.patch

@@ -1,19 +1,24 @@
-From 9a6f74102c35e60f0f9298d417593f6cf4baa3c8 Mon Sep 17 00:00:00 2001
+From fc7a850da707cd0f00c21638a47104492bb8cf32 Mon Sep 17 00:00:00 2001
 From: Kondapally Kalyan <kalyan.kondapally@intel.com>
-Date: Fri, 4 Oct 2013 11:39:08 +0300
+Date: Fri, 29 Nov 2013 13:24:43 +0200
 Subject: [PATCH] Chromium-Add-gl-changes-for-Wayland.
 
-This patch adds basic support needed in NativeViewGLSurfaceEGL to resize window.
-Changes related to resizing needs more testing before trying to upstream the patch.
+This patch adds following support:
+1)Support needed in NativeViewGLSurfaceEGL to resize window.
+  Changes related to resizing needs more testing before
+  trying to upstream the patch.
+2)OffScreen-rendering support for use cases like WebGL and
+  Canvas2D. This should be enabled in upstream but needs some
+  cross platform support before it can be done.
 ---
- ui/gl/gl_surface_egl.cc |   13 +++++++++++--
- 1 file changed, 11 insertions(+), 2 deletions(-)
+ ui/gl/gl_surface_egl.cc |   14 +++++++++++---
+ 1 file changed, 11 insertions(+), 3 deletions(-)
 
 diff --git a/ui/gl/gl_surface_egl.cc b/ui/gl/gl_surface_egl.cc
-index 0c1871e..9e5f7f5 100644
+index 3f8923a..92087af 100644
 --- a/ui/gl/gl_surface_egl.cc
 +++ b/ui/gl/gl_surface_egl.cc
-@@ -116,8 +116,7 @@ bool GLSurfaceEGL::InitializeOneOff() {
+@@ -118,8 +118,7 @@ bool GLSurfaceEGL::InitializeOneOff() {
      LOG(ERROR) << "OZONE failed to initialize hardware";
      return false;
    }
@@ -23,15 +28,7 @@ index 0c1871e..9e5f7f5 100644
  #else
    g_native_display = EGL_DEFAULT_DISPLAY;
  #endif
-@@ -394,6 +393,7 @@ bool NativeViewGLSurfaceEGL::Resize(const gfx::Size& size) {
-   GLContext* current_context = GLContext::GetCurrent();
-   bool was_current =
-       current_context && current_context->IsCurrent(this);
-+
-   if (was_current) {
-     scoped_make_current.reset(
-         new ui::ScopedMakeCurrent(current_context, this));
-@@ -402,6 +402,15 @@ bool NativeViewGLSurfaceEGL::Resize(const gfx::Size& size) {
+@@ -432,6 +431,15 @@ bool NativeViewGLSurfaceEGL::Resize(const gfx::Size& size) {
 
    Destroy();
 
@@ -47,6 +44,15 @@ index 0c1871e..9e5f7f5 100644
    if (!Initialize()) {
      LOG(ERROR) << "Failed to resize window.";
      return false;
+@@ -750,7 +758,7 @@ GLSurface::CreateOffscreenGLSurface(const gfx::Size& size) {
+     case kGLImplementationEGLGLES2: {
+       scoped_refptr<GLSurface> surface;
+       if (g_egl_surfaceless_context_supported &&
+-         (size.width() == 0 && size.height() == 0)) {
++         (size.width() == 1 && size.height() == 1)) {
+         surface = new SurfacelessEGL(size);
+       } else
+         surface = new PbufferGLSurfaceEGL(size);
 -- 
 1.7.9.5