Fix unconditionally supporting derivative functions in ES3.

TRAC #23377
Signed-off-by: Jamie Madill
Signed-off-by: Shannon Woods
Author: Nicolas Capens
diff --git a/src/compiler/Initialize.cpp b/src/compiler/Initialize.cpp
index d2b92ea..826c6fc 100644
--- a/src/compiler/Initialize.cpp
+++ b/src/compiler/Initialize.cpp
@@ -591,15 +591,15 @@
             symbolTable.relateToExtension(ESSL1_BUILTINS, "dFdx", "GL_OES_standard_derivatives");
             symbolTable.relateToExtension(ESSL1_BUILTINS, "dFdy", "GL_OES_standard_derivatives");
             symbolTable.relateToExtension(ESSL1_BUILTINS, "fwidth", "GL_OES_standard_derivatives");
-
-            symbolTable.relateToOperator(ESSL3_BUILTINS, "dFdx",   EOpDFdx);
-            symbolTable.relateToOperator(ESSL3_BUILTINS, "dFdy",   EOpDFdy);
-            symbolTable.relateToOperator(ESSL3_BUILTINS, "fwidth", EOpFwidth);
         }
         break;
     default: break;
     }
 
+    symbolTable.relateToOperator(ESSL3_BUILTINS, "dFdx",   EOpDFdx);
+    symbolTable.relateToOperator(ESSL3_BUILTINS, "dFdy",   EOpDFdy);
+    symbolTable.relateToOperator(ESSL3_BUILTINS, "fwidth", EOpFwidth);
+
     // Finally add resource-specific variables.
     switch(type) {
     case SH_FRAGMENT_SHADER: