Load the GL_KHR_debug entry points and log messages they produce.

gpu/command_buffer/service/feature_info.cc

Index: gpu/command_buffer/service/feature_info.cc
diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index 34750b01a42a7ee15bc5d4928cc1a18e29b7dbde..40ee28fbd7a1229cc06d23dbf1351b2241b48d82 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -1401,6 +1401,10 @@ void FeatureInfo::InitializeFeatures() {
 
   feature_flags_.angle_robust_client_memory =
       extensions.Contains("GL_ANGLE_robust_client_memory");
+
+  feature_flags_.khr_debug = gl_version_info_->IsAtLeastGL(4, 3) ||
+                             gl_version_info_->IsAtLeastGLES(3, 2) ||
+                             extensions.Contains("GL_KHR_debug");
 }
 
 bool FeatureInfo::IsES3Capable() const {