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/gpu/ccpr/GrCCPRCoverageProcessor.h b/src/gpu/ccpr/GrCCPRCoverageProcessor.h
index b8032d9..8120136 100644
--- a/src/gpu/ccpr/GrCCPRCoverageProcessor.h
+++ b/src/gpu/ccpr/GrCCPRCoverageProcessor.h
@@ -133,9 +133,9 @@
 
     PrimitiveProcessor(CoverageType coverageType)
             : fCoverageType(coverageType)
-            , fGeomWind("wind", kFloat_GrSLType, GrShaderVar::kNonArray, kLow_GrSLPrecision)
-            , fFragWind(kFloat_GrSLType)
-            , fFragCoverageTimesWind(kFloat_GrSLType) {}
+            , fGeomWind("wind", kHalf_GrSLType, GrShaderVar::kNonArray, kLow_GrSLPrecision)
+            , fFragWind(kHalf_GrSLType)
+            , fFragCoverageTimesWind(kHalf_GrSLType) {}
 
     // Called before generating shader code. Subclass should add its custom varyings to the handler
     // and update its corresponding internal member variables.