Implement GL_EXT_debug_marker for RendererGL.

src/libANGLE/renderer/gl/RendererGL.cpp

@@ -303,19 +303,20 @@ SamplerImpl *RendererGL::createSampler()
     return new SamplerGL(mFunctions, mStateManager);
 }
 
-void RendererGL::insertEventMarker(GLsizei, const char *)
+void RendererGL::insertEventMarker(GLsizei length, const char *marker)
 {
-    UNREACHABLE();
+    mFunctions->debugMessageInsert(GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_MARKER, 0,
+                                   GL_DEBUG_SEVERITY_NOTIFICATION, length, marker);
 }
 
-void RendererGL::pushGroupMarker(GLsizei, const char *)
+void RendererGL::pushGroupMarker(GLsizei length, const char *marker)
 {
-    UNREACHABLE();
+    mFunctions->pushDebugGroup(GL_DEBUG_SOURCE_APPLICATION, 0, length, marker);
 }
 
 void RendererGL::popGroupMarker()
 {
-    UNREACHABLE();
+    mFunctions->popDebugGroup();
 }
 
 void RendererGL::notifyDeviceLost()

src/libANGLE/renderer/gl/renderergl_utils.cpp

@@ -544,6 +544,9 @@ void GenerateCaps(const FunctionsGL *functions, gl::Caps *caps, gl::TextureCapsM
     extensions->packSubimage = functions->standard == STANDARD_GL_DESKTOP ||
                                functions->isAtLeastGLES(gl::Version(3, 0)) ||
                                functions->hasGLESExtension("GL_NV_pack_subimage");
+    extensions->debugMarker =
+        functions->isAtLeastGL(gl::Version(4, 3)) || functions->hasGLExtension("GL_KHR_debug") ||
+        functions->isAtLeastGLES(gl::Version(3, 2)) || functions->hasGLESExtension("GL_KHR_debug");
 }
 
 void GenerateWorkarounds(const FunctionsGL *functions, WorkaroundsGL *workarounds)