automatically generate clone() methods for SkSL fragment processors

Bug: skia:
Change-Id: Ib7b90f20d2b1558aad14f38f95c7c884e654c96d
Reviewed-on: https://skia-review.googlesource.com/28620
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/src/sksl/SkSLCPPCodeGenerator.h b/src/sksl/SkSLCPPCodeGenerator.h
index 8b30151..b4f31ba 100644
--- a/src/sksl/SkSLCPPCodeGenerator.h
+++ b/src/sksl/SkSLCPPCodeGenerator.h
@@ -27,7 +27,7 @@
 
     void writef(const char* s, ...) SKSL_PRINTF_LIKE(2, 3);
 
-    void writeSection(const char* name, const char* prefix = "");
+    bool writeSection(const char* name, const char* prefix = "");
 
     void writeHeader() override;
 
@@ -72,6 +72,8 @@
 
     void writeGetKey();
 
+    void writeClone();
+
     void writeTest();
 
     String fName;