Allow derivative functions if derivative extension is enabled. I still need to add validation for "#extension GL_OES_standard_derivatives : enable".
BUG=25
Review URL: http://codereview.appspot.com/1965045

git-svn-id: https://angleproject.googlecode.com/svn/trunk@403 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/compiler/OutputHLSL.cpp b/src/compiler/OutputHLSL.cpp
index 8b8a4e6..0bb73d4 100644
--- a/src/compiler/OutputHLSL.cpp
+++ b/src/compiler/OutputHLSL.cpp
@@ -933,9 +933,9 @@
       case EOpFract:            outputTriplet(visit, "frac(", "", ")");      break;
       case EOpLength:           outputTriplet(visit, "length(", "", ")");    break;
       case EOpNormalize:        outputTriplet(visit, "normalize(", "", ")"); break;
-//    case EOpDPdx:             outputTriplet(visit, "ddx(", "", ")");       break;
-//    case EOpDPdy:             outputTriplet(visit, "ddy(", "", ")");       break;
-//    case EOpFwidth:           outputTriplet(visit, "fwidth(", "", ")");    break;        
+      case EOpDFdx:             outputTriplet(visit, "ddx(", "", ")");       break;
+      case EOpDFdy:             outputTriplet(visit, "ddy(", "", ")");       break;
+      case EOpFwidth:           outputTriplet(visit, "fwidth(", "", ")");    break;        
       case EOpAny:              outputTriplet(visit, "any(", "", ")");       break;
       case EOpAll:              outputTriplet(visit, "all(", "", ")");       break;
       default: UNREACHABLE();