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 23 matching lines @@
         GLSurfaceWGL::GetDisplayDC());
   } else if (g_driver_wgl.fn.wglGetExtensionsStringEXTFn) {
     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() {
+#if defined(OS_WIN)
+  EGLDisplay display = GLSurfaceEGL::InitializeDisplay();
+  if (display == EGL_NO_DISPLAY)
+    return "";

[Jamie Madill, 2015/04/20 18:33:11]

I wasn't sure if I should put the NO_DISPLAY check in the main body of the
function, because it theoretically would change the behaviour of the function on
non-Windows platforms.

[Zhenyao Mo, 2015/04/20 19:51:47]

If display isn't valid, eglQueryString just return NULL. So probably you can
unify the WIN and non WIN path behaviors.

[Jamie Madill, 2015/04/20 20:20:09]

One difference - if display is EGL_NO_DISPLAY and the EGL platform supports
EGL_EXT_client_extensions (or EGL 1.5), the EGL will return a list of client
extensions. (See GetClientExtensions below). I think in either case it makes
sense to unify, thanks.

+#else
   EGLDisplay display =
-#if defined(OS_WIN)
-    GLSurfaceEGL::GetPlatformDisplay(GetPlatformDefaultEGLNativeDisplay());
-#else
-    g_driver_egl.fn.eglGetDisplayFn(GetPlatformDefaultEGLNativeDisplay());
+      g_driver_egl.fn.eglGetDisplayFn(GetPlatformDefaultEGLNativeDisplay());
+  DCHECK(g_driver_egl.fn.eglInitializeFn);
+  g_driver_egl.fn.eglInitializeFn(display, NULL, NULL);
 #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() {
   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