re-land of new SkSL precisions

Bug: skia:
Change-Id: Ic1deb3db2cbda6ca45f93dee99832971a36a2119
Reviewed-on: https://skia-review.googlesource.com/47841
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
diff --git a/src/sksl/SkSLCPPCodeGenerator.h b/src/sksl/SkSLCPPCodeGenerator.h
index 27b434a..6727b9c 100644
--- a/src/sksl/SkSLCPPCodeGenerator.h
+++ b/src/sksl/SkSLCPPCodeGenerator.h
@@ -31,9 +31,9 @@
 
     void writeHeader() override;
 
-    void writePrecisionModifier() override;
+    bool usesPrecisionModifiers() const override;
 
-    void writeType(const Type& type) override;
+    String getTypeName(const Type& type) override;
 
     void writeBinaryExpression(const BinaryExpression& b, Precedence parentPrecedence) override;