Check that the requested extension is supported by the backend.

src/libANGLE/Context.cpp

@@ -2566,12 +2566,23 @@ size_t Context::getExtensionStringCount() const
     return mExtensionStrings.size();
 }
 
+bool Context::isExtensionRequestable(const char *name)
+{
+    const ExtensionInfoMap &extensionInfos = GetExtensionInfoMap();
+    auto extension                         = extensionInfos.find(name);
+
+    const Extensions &nativeExtensions = mImplementation->getNativeExtensions();
+    return extension != extensionInfos.end() && extension->second.Requestable &&
+           nativeExtensions.*(extension->second.ExtensionsMember);
+}
+
 void Context::requestExtension(const char *name)
 {
     const ExtensionInfoMap &extensionInfos = GetExtensionInfoMap();
     ASSERT(extensionInfos.find(name) != extensionInfos.end());
     const auto &extension = extensionInfos.at(name);
     ASSERT(extension.Requestable);
+    ASSERT(mImplementation->getNativeExtensions().*(extension.ExtensionsMember));
 
     if (mExtensions.*(extension.ExtensionsMember))
     {

src/libANGLE/Context.h

@@ -909,6 +909,7 @@ class Context final : public ValidationContext
 
     size_t getExtensionStringCount() const;
 
+    bool isExtensionRequestable(const char *name);
     void requestExtension(const char *name);
     size_t getRequestableExtensionStringCount() const;
 

src/libANGLE/renderer/null/ContextNULL.cpp

@@ -69,6 +69,7 @@ ContextNULL::ContextNULL(const gl::ContextState &state, AllocationTrackerNULL *a
 
     mExtensions                       = gl::Extensions();
     mExtensions.fence                 = true;
+    mExtensions.instancedArrays       = true;
     mExtensions.pixelBufferObject     = true;
     mExtensions.mapBuffer             = true;
     mExtensions.mapBufferRange        = true;

src/libANGLE/validationES2.cpp

@@ -4224,7 +4224,7 @@ bool ValidateBufferSubData(ValidationContext *context,
     return true;
 }
 
-bool ValidateRequestExtensionANGLE(ValidationContext *context, const GLchar *name)
+bool ValidateRequestExtensionANGLE(Context *context, const GLchar *name)
 {
     if (!context->getExtensions().requestExtension)
     {
@@ -4232,9 +4232,7 @@ bool ValidateRequestExtensionANGLE(ValidationContext *context, const GLchar *nam
         return false;
     }
 
-    const ExtensionInfoMap &extensionInfos = GetExtensionInfoMap();
-    auto extension                         = extensionInfos.find(name);
-    if (extension == extensionInfos.end() || !extension->second.Requestable)
+    if (!context->isExtensionRequestable(name))
     {
         context->handleError(InvalidOperation() << "Extension " << name << " is not requestable.");
         return false;

src/libANGLE/validationES2.h

@@ -357,7 +357,7 @@ bool ValidateBufferSubData(ValidationContext *context,
                            GLsizeiptr size,
                            const void *data);
 
-bool ValidateRequestExtensionANGLE(ValidationContext *context, const GLchar *name);
+bool ValidateRequestExtensionANGLE(Context *context, const GLchar *name);
 
 bool ValidateActiveTexture(ValidationContext *context, GLenum texture);
 bool ValidateAttachShader(ValidationContext *context, GLuint program, GLuint shader);