Support ozone=1 compositor_unittests with OSMesa

ui/gl/gl_surface_egl.cc

Index: ui/gl/gl_surface_egl.cc
diff --git a/ui/gl/gl_surface_egl.cc b/ui/gl/gl_surface_egl.cc
index b99b7b4942c575610495eeac35f79b1a1d69d3bc..b2da76247828675f2159501bd0827fb38d02e765 100644
--- a/ui/gl/gl_surface_egl.cc
+++ b/ui/gl/gl_surface_egl.cc
@@ -15,6 +15,7 @@
 #include "ui/gl/egl_util.h"
 #include "ui/gl/gl_context.h"
 #include "ui/gl/gl_implementation.h"
+#include "ui/gl/gl_surface_osmesa.h"
 #include "ui/gl/gl_surface_stub.h"
 #include "ui/gl/scoped_make_current.h"
 
@@ -564,6 +565,9 @@ PbufferGLSurfaceEGL::~PbufferGLSurfaceEGL() {
 
 // static
 bool GLSurface::InitializeOneOffInternal() {
+  if (GetGLImplementation() == kGLImplementationOSMesaGL) {
+    return true;
+  }
   DCHECK(GetGLImplementation() == kGLImplementationEGLGLES2);
 
   if (!GLSurfaceEGL::InitializeOneOff()) {
@@ -576,6 +580,13 @@ bool GLSurface::InitializeOneOffInternal() {
 // static
 scoped_refptr<GLSurface>
 GLSurface::CreateViewGLSurface(gfx::AcceleratedWidget window) {
+
+  if (GetGLImplementation() == kGLImplementationOSMesaGL) {
+    scoped_refptr<GLSurface> surface(new GLSurfaceOSMesaHeadless(window));

[jonathan.backer, 2013/06/27 17:13:28]

Can we define this class in an anonymous namespace in this file? There's no need
for the rest of the world to know about it. This is what we do for
NativeViewGLSurfaceOSMesa.

[rjkroege, 2013/06/28 00:25:01]

Yes. But there is a difficulty around this. gl_surface_osmesa.cc needs a #define
from osmesa.h. But osmesa.h cannot be compiled in if it follows gl_bindings.h as
the EGL include files destructively alter the necessary pre-reqs. So: I cannot
put GLSurfaceOSMesaHeadless in gl_surface_egl.cc without either:

*  hard-coding a OSMesa constant in gl_surface_egl.cc
*  egregious include order violation

or I can leave it like this. Thoughts?

[jonathan.backer, 2013/06/28 13:13:47]

Thanks for the explanation. I have a slight preference for an include order
violation (it'll be in a .cc file) because I don't like exposing more than
necessary in a .h. We've had similar ordering violations with X includes and
we've just lumped it. If you choose to violate include order, just add a comment
why so no one bothers to try to clean it up.

That's just my dogma. Feel free to choose your own.

+    if (!surface->Initialize())
+      return NULL;
+    return surface;
+  }
   DCHECK(GetGLImplementation() == kGLImplementationEGLGLES2);
   if (window) {
     scoped_refptr<NativeViewGLSurfaceEGL> surface;
@@ -601,6 +612,13 @@ GLSurface::CreateViewGLSurface(gfx::AcceleratedWidget window) {
 scoped_refptr<GLSurface>
 GLSurface::CreateOffscreenGLSurface(const gfx::Size& size) {
   switch (GetGLImplementation()) {
+    case kGLImplementationOSMesaGL: {
+      scoped_refptr<GLSurface> surface(new GLSurfaceOSMesa(1, size));
+      if (!surface->Initialize())
+        return NULL;
+
+      return surface;
+    }
     case kGLImplementationEGLGLES2: {
       scoped_refptr<PbufferGLSurfaceEGL> surface(
           new PbufferGLSurfaceEGL(size));