Disable GL_OES_standard_derivatives when ps_2_x or later is not available.

BUG=392
Review URL: https://codereview.appspot.com/7027051


Author:    bsalomon@google.com

(manual merge from master by daniel@transgaming.com)

git-svn-id: https://angleproject.googlecode.com/svn/branches/dx11proto@1704 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/libGLESv2/renderer/Renderer11.cpp b/src/libGLESv2/renderer/Renderer11.cpp
index 860a35e..9e71cb7 100644
--- a/src/libGLESv2/renderer/Renderer11.cpp
+++ b/src/libGLESv2/renderer/Renderer11.cpp
@@ -1414,6 +1414,13 @@
     return false && !gl::perfActive();
 }
 
+bool Renderer11::getDerivativeInstructionSupport() const
+{
+    // TODO
+    // UNIMPLEMENTED();
+    return false;
+}
+
 int Renderer11::getMajorShaderModel() const
 {
     switch (mFeatureLevel)