Enable stencil clipping in mixed sampled render targets

src/gpu/gl/GrGLInterface.cpp

Index: src/gpu/gl/GrGLInterface.cpp
diff --git a/src/gpu/gl/GrGLInterface.cpp b/src/gpu/gl/GrGLInterface.cpp
index ec51797c7e81cf246b0c39e5df4878414d4c8e87..77a7f9bbe5ca4b127d58b69d5c231688fe37d148 100644
--- a/src/gpu/gl/GrGLInterface.cpp
+++ b/src/gpu/gl/GrGLInterface.cpp
@@ -701,6 +701,18 @@ bool GrGLInterface::validate() const {
         }
     }
 
+    if (kGL_GrGLStandard == fStandard && glVer >= GR_GL_VER(4,5)) {
+        if (nullptr == fFunctions.fNamedFramebufferParameteri) {
+            RETURN_FALSE_INTERFACE
+        }
+    }
+
+    if (fExtensions.has("GL_NV_sample_locations")) {
+        if (nullptr == fFunctions.fNamedFramebufferSampleLocationsfv) {
+            RETURN_FALSE_INTERFACE
+        }
+    }
+
     if ((kGL_GrGLStandard == fStandard && glVer >= GR_GL_VER(4,3)) ||
         fExtensions.has("GL_KHR_debug")) {
         if (nullptr == fFunctions.fDebugMessageControl ||