Refactor GL bindings so there is no global GLApi or DriverGL.

ui/gl/gl_context_stub.cc

Index: ui/gl/gl_context_stub.cc
diff --git a/ui/gl/gl_context_stub.cc b/ui/gl/gl_context_stub.cc
index a72f08080cc06d5b3f7c341c6bd1e9480a046316..1c54f9dd42c1d4263c6a4862b8b38998ebe62ce0 100644
--- a/ui/gl/gl_context_stub.cc
+++ b/ui/gl/gl_context_stub.cc
@@ -5,12 +5,16 @@
 #include "ui/gl/gl_context_stub.h"
 
 #include "ui/gl/gl_gl_api_implementation.h"
+#include "ui/gl/gl_stub_api.h"
 
 namespace gl {
 
-GLContextStub::GLContextStub() : GLContextReal(nullptr) {}
+GLContextStub::GLContextStub() : GLContextStub(nullptr) {}
 GLContextStub::GLContextStub(GLShareGroup* share_group)
-    : GLContextReal(share_group) {}
+    : GLContextReal(share_group),
+      use_stub_api_(false),
+      version_str_("OpenGL ES 3.0"),
+      extensions_("GL_EXT_framebuffer_object") {}
 
 bool GLContextStub::Initialize(GLSurface* compatible_surface,
                                const GLContextAttribs& attribs) {
@@ -18,7 +22,7 @@ bool GLContextStub::Initialize(GLSurface* compatible_surface,
 }
 
 bool GLContextStub::MakeCurrent(GLSurface* surface) {
-  SetGLToStubGLApi();
+  BindGLApi();
   SetCurrent(surface);
   InitializeDynamicBindings();
   return true;
@@ -39,10 +43,50 @@ void* GLContextStub::GetHandle() {
 void GLContextStub::OnSetSwapInterval(int interval) {
 }
 
+std::string GLContextStub::GetGLVersion() {
+  return version_str_;
+}
+
 std::string GLContextStub::GetGLRenderer() {
   return std::string("CHROMIUM");
 }
 
+bool GLContextStub::WasAllocatedUsingRobustnessExtension() {
+  return HasExtension("GL_ARB_robustness") ||
+         HasExtension("GL_KHR_robustness") || HasExtension("GL_EXT_robustness");
+}
+
+std::string GLContextStub::GetExtensions() {
+  return extensions_;
+}
+
+void GLContextStub::SetUseStubApi(bool stub_api) {
+  use_stub_api_ = stub_api;
+}
+
+void GLContextStub::SetExtensionsString(const char* extensions) {
+  extensions_ = extensions;
+}
+
+void GLContextStub::SetGLVersionString(const char* version_str) {
+  version_str_ = std::string(version_str ? version_str : "");
+}
+
 GLContextStub::~GLContextStub() {}
 
+GLApi* GLContextStub::CreateGLApi(DriverGL* driver) {
+  if (use_stub_api_) {
+    GLStubApi* stub_api = new GLStubApi();
+    if (!version_str_.empty()) {
+      stub_api->set_version(version_str_);
+    }
+    if (!extensions_.empty()) {
+      stub_api->set_extensions(extensions_);
+    }
+    return stub_api;
+  }
+
+  return GLContext::CreateGLApi(driver);
+}
+
 }  // namespace gl