fixed early return breaking things in .fp files

Bug: skia:
Change-Id: If91e8cb2f312cb7546967bd9af0d1ae180177870
Reviewed-on: https://skia-review.googlesource.com/146644
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
diff --git a/src/sksl/SkSLCPPCodeGenerator.h b/src/sksl/SkSLCPPCodeGenerator.h
index 40d9982..014f917 100644
--- a/src/sksl/SkSLCPPCodeGenerator.h
+++ b/src/sksl/SkSLCPPCodeGenerator.h
@@ -49,6 +49,8 @@
 
     void writeIfStatement(const IfStatement& s) override;
 
+    void writeReturnStatement(const ReturnStatement& s) override;
+
     void writeSwitchStatement(const SwitchStatement& s) override;
 
     void writeFunctionCall(const FunctionCall& c) override;
@@ -92,6 +94,7 @@
     std::set<int> fWrittenTransformedCoords;
     // if true, we are writing a C++ expression instead of a GLSL expression
     bool fCPPMode = false;
+    bool fInMain = false;
 
     typedef GLSLCodeGenerator INHERITED;
 };