Detect function recursion and reject a shader if detected.

ANGLEBUG=191
TEST=shaders with function recursion are rejected.
Review URL: http://codereview.appspot.com/4808061

git-svn-id: https://angleproject.googlecode.com/svn/trunk@711 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/compiler/ShHandle.h b/src/compiler/ShHandle.h
index bf61d29..76c53bc 100644
--- a/src/compiler/ShHandle.h
+++ b/src/compiler/ShHandle.h
@@ -66,6 +66,8 @@
     bool InitBuiltInSymbolTable(const ShBuiltInResources& resources);
     // Clears the results from the previous compilation.
     void clearResults();
+    // Return true if function recursion is detected.
+    bool detectRecursion(TIntermNode* root);
     // Returns true if the given shader does not exceed the minimum
     // functionality mandated in GLSL 1.0 spec Appendix A.
     bool validateLimitations(TIntermNode* root);