Make addUniform take a precision

src/effects/SkMagnifierImageFilter.cpp

Index: src/effects/SkMagnifierImageFilter.cpp
diff --git a/src/effects/SkMagnifierImageFilter.cpp b/src/effects/SkMagnifierImageFilter.cpp
index 1f8947331f2133af7f5143ef05e69a0a98c19fdb..ae6637b28227f12b7b09fa4500b310737b7ff598 100644
--- a/src/effects/SkMagnifierImageFilter.cpp
+++ b/src/effects/SkMagnifierImageFilter.cpp
@@ -125,15 +125,15 @@ void GrGLMagnifierEffect::emitCode(GrGLFPBuilder* builder,
     fOffsetVar = builder->addUniform(
         GrGLProgramBuilder::kFragment_Visibility |
         GrGLProgramBuilder::kVertex_Visibility,
-        kVec2f_GrSLType, "Offset");
+        kVec2f_GrSLType, kDefault_GrSLPrecision, "Offset");
     fInvZoomVar = builder->addUniform(
         GrGLProgramBuilder::kFragment_Visibility |
         GrGLProgramBuilder::kVertex_Visibility,
-        kVec2f_GrSLType, "InvZoom");
+        kVec2f_GrSLType, kDefault_GrSLPrecision, "InvZoom");
     fInvInsetVar = builder->addUniform(
         GrGLProgramBuilder::kFragment_Visibility |
         GrGLProgramBuilder::kVertex_Visibility,
-        kVec2f_GrSLType, "InvInset");
+        kVec2f_GrSLType, kDefault_GrSLPrecision, "InvInset");
 
     GrGLFPFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
     SkString coords2D = fsBuilder->ensureFSCoords2D(coords, 0);