gpu: Upgrade to new ANGLE Platform Display init.

ui/gl/gl_bindings.cc

 // Copyright 2014 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.
 
 #if defined(OS_WIN) || defined(USE_X11) || defined(OS_ANDROID) || defined(USE_OZONE)
 #include <EGL/egl.h>
 #endif
 
 #include "ui/gl/gl_bindings.h"
 
@@ skipping 25 matching lines @@
     str = g_driver_wgl.fn.wglGetExtensionsStringEXTFn();
   }
   return str ? std::string(str) : "";
 }
 #endif
 
 #if defined(OS_WIN) || defined(USE_X11) || defined(OS_ANDROID) || defined(USE_OZONE)
 std::string DriverEGL::GetPlatformExtensions() {
   EGLDisplay display =
 #if defined(OS_WIN)
-    GLSurfaceEGL::GetPlatformDisplay(GetPlatformDefaultEGLNativeDisplay());
+      GLSurfaceEGL::InitializeDisplay();
+  if (display == EGL_NO_DISPLAY)
+    return "";
 #else
-    g_driver_egl.fn.eglGetDisplayFn(GetPlatformDefaultEGLNativeDisplay());
+      g_driver_egl.fn.eglGetDisplayFn(GetPlatformDefaultEGLNativeDisplay());
+  if (display == EGL_NO_DISPLAY)
+    return "";
+  DCHECK(g_driver_egl.fn.eglInitializeFn);
+  g_driver_egl.fn.eglInitializeFn(display, NULL, NULL);

[piman, 2015/04/23 21:03:30]

It would be easier to follow if both OS_WIN and !OS_WIN went through the same
path here, i.e. have GLSurfaceEGL::InitializeDisplay be exposed on both - on
!OS_WIN it would simply do the eglGetDisplay and eglInitialize. That could even
be reused in GLSurfaceEGL::InitializeOneOff

 #endif
 
-  DCHECK(g_driver_egl.fn.eglInitializeFn);
-  g_driver_egl.fn.eglInitializeFn(display, NULL, NULL);
   DCHECK(g_driver_egl.fn.eglQueryStringFn);
   const char* str = g_driver_egl.fn.eglQueryStringFn(display, EGL_EXTENSIONS);
   return str ? std::string(str) : "";
 }
 
 // static
 std::string DriverEGL::GetClientExtensions() {
+  DCHECK(g_driver_egl.fn.eglQueryStringFn);
   const char* str =
       g_driver_egl.fn.eglQueryStringFn(EGL_NO_DISPLAY, EGL_EXTENSIONS);
   return str ? std::string(str) : "";
 }
 #endif
 
 #if defined(USE_X11)
 std::string DriverGLX::GetPlatformExtensions() {
   DCHECK(g_driver_glx.fn.glXQueryExtensionsStringFn);
   const char* str =
       g_driver_glx.fn.glXQueryExtensionsStringFn(gfx::GetXDisplay(), 0);
   return str ? std::string(str) : "";
 }
 #endif
 
 }  // namespace gfx