Expose GLES2Interface to blink, and delete isContextLost() from WGC3D.

third_party/WebKit/public/platform/WebGraphicsContext3D.h

Index: third_party/WebKit/public/platform/WebGraphicsContext3D.h
diff --git a/third_party/WebKit/public/platform/WebGraphicsContext3D.h b/third_party/WebKit/public/platform/WebGraphicsContext3D.h
index cd8a5d46cf662c5e27c686190895cb70673e3d39..89ad941ddcb143cb256f57655f156a67f3411fa5 100644
--- a/third_party/WebKit/public/platform/WebGraphicsContext3D.h
+++ b/third_party/WebKit/public/platform/WebGraphicsContext3D.h
@@ -35,6 +35,12 @@
 #include "WebNonCopyable.h"
 #include "WebString.h"
 
+namespace gpu {
+namespace gles2 {
+class GLES2Interface;
+}
+}
+
 struct GrGLInterface;
 
 namespace blink {
@@ -169,8 +175,6 @@ public:
     // getError in the order they were added.
     virtual void synthesizeGLError(WGC3Denum) = 0;
 
-    virtual bool isContextLost() = 0;
-
     // GL_CHROMIUM_map_sub
     virtual void* mapBufferSubDataCHROMIUM(WGC3Denum target, WGC3Dintptr offset, WGC3Dsizeiptr size, WGC3Denum access) = 0;
     virtual void unmapBufferSubDataCHROMIUM(const void*) = 0;
@@ -550,6 +554,9 @@ public:
     virtual void vertexAttribI4uiv(WGC3Duint index, const WGC3Duint *v) { }
     virtual void vertexAttribIPointer(WGC3Duint index, WGC3Dint size, WGC3Denum type, WGC3Dsizei stride, WGC3Dintptr pointer) { }
     virtual void waitSync(WGC3Dsync sync, WGC3Dbitfield flags, WGC3Duint64 timeout) { }
+
+    // Prefer getting a GLES2Interface off WebGraphicsContext3DProvider if possible, and avoid using WebGraphicsContext3D at all.
+    virtual gpu::gles2::GLES2Interface* getGLES2Interface() = 0;
 };
 
 } // namespace blink