Add a --use-angle flag for selecting the ANGLE renderer.

ui/gl/gl_switches.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_switches.h"
 #include "base/basictypes.h"
 
 namespace gfx {
 
 const char kGLImplementationDesktopName[]     = "desktop";
 const char kGLImplementationOSMesaName[]      = "osmesa";
 const char kGLImplementationAppleName[]       = "apple";
 const char kGLImplementationEGLName[]         = "egl";
 const char kGLImplementationSwiftShaderName[] = "swiftshader";
 const char kGLImplementationMockName[]        = "mock";
 
+const char kANGLEImplementationDefaultName[]  = "default";
+const char kANGLEImplementationD3D9Name[]     = "d3d9";
+const char kANGLEImplementationD3D11Name[]    = "d3d11";
+const char kANGLEImplementationWARPName[]     = "warp";
+const char kANGLEImplementationOpenGLName[]   = "gl";
+const char kANGLEImplementationOpenGLESName[] = "gles";
+
 }  // namespace gfx
 
 namespace switches {
 
 // Disables use of D3D11.
 const char kDisableD3D11[]                  = "disable-d3d11";
 
 // Stop the GPU from synchronizing on the vsync before presenting.
 const char kDisableGpuVsync[]               = "disable-gpu-vsync";
 
 // Turns on GPU logging (debug build only).
 const char kEnableGPUServiceLogging[]       = "enable-gpu-service-logging";
 
 // Turns on calling TRACE for every GL call.
 const char kEnableGPUServiceTracing[]       = "enable-gpu-service-tracing";
 
+// Select which ANGLE backend to use. Options are:
+//  default: Attempts several ANGLE renderers until one successfully
+//           initializes, varying ES support by platform.
+//  d3d9: Legacy D3D9 renderer, ES2 only.
+//  d3d11: D3D11 renderer, ES2 and ES3.
+//  warp: D3D11 renderer using software rasterization, ES2 and ES3.
+//  gl: Desktop GL renderer, ES2 and ES3.
+//  gles: GLES renderer, ES2 and ES3.
+const char kUseANGLE[]                      = "use-angle";
+
 // Select which implementation of GL the GPU process should use. Options are:
 //  desktop: whatever desktop OpenGL the user has installed (Linux and Mac
 //           default).
 //  egl: whatever EGL / GLES2 the user has installed (Windows default - actually
 //       ANGLE).
 //  osmesa: The OSMesa software renderer.
 const char kUseGL[]                         = "use-gl";
 
 const char kSwiftShaderPath[]               = "swiftshader-path";
 
 // Inform Chrome that a GPU context will not be lost in power saving mode,
 // screen saving mode, etc.  Note that this flag does not ensure that a GPU
 // context will never be lost in any situations, say, a GPU reset.
 const char kGpuNoContextLost[]              = "gpu-no-context-lost";
 
 // Indicates whether the dual GPU switching is supported or not.
 const char kSupportsDualGpus[]              = "supports-dual-gpus";
 
 // Flag used for Linux tests: for desktop GL bindings, try to load this GL
 // library first, but fall back to regular library if loading fails.
 const char kTestGLLib[]                     = "test-gl-lib";
 
 // Use hardware gpu, if available, for tests.
 const char kUseGpuInTests[] = "use-gpu-in-tests";
 
-// On Windows only: use the WARP software rasterizer in the GPU process.
-const char kUseWarp[] = "use-warp";

[Jamie Madill, 2015/05/07 18:53:13]

you might want to check with someone about disabling this flag

-
 // Enable OpenGL ES 3 APIs without proper service side validation.
 const char kEnableUnsafeES3APIs[] = "enable-unsafe-es3-apis";
 
 // Disables GL drawing operations which produce pixel output. With this
 // the GL output will not be correct but tests will run faster.
 const char kDisableGLDrawingForTests[] = "disable-gl-drawing-for-tests";
 
 // Forces the use of OSMesa instead of hardware gpu.
 const char kOverrideUseGLWithOSMesaForTests[] =
     "override-use-gl-with-osmesa-for-tests";
 
 // This is the list of switches passed from this file that are passed from the
 // GpuProcessHost to the GPU Process. Add your switch to this list if you need
 // to read it in the GPU process, else don't add it.
 const char* kGLSwitchesCopiedFromGpuProcessHost[] = {
   kDisableGpuVsync,
   kDisableD3D11,
   kEnableGPUServiceLogging,
   kEnableGPUServiceTracing,
   kEnableUnsafeES3APIs,
   kGpuNoContextLost,
   kDisableGLDrawingForTests,
   kOverrideUseGLWithOSMesaForTests,
-  kUseWarp,
+  kUseANGLE,
 };
 const int kGLSwitchesCopiedFromGpuProcessHostNumSwitches =
     arraysize(kGLSwitchesCopiedFromGpuProcessHost);
 
 }  // namespace switches