create GrTestUtils.h, move some common functions into it

src/gpu/effects/GrDashingEffect.cpp

Index: src/gpu/effects/GrDashingEffect.cpp
diff --git a/src/gpu/effects/GrDashingEffect.cpp b/src/gpu/effects/GrDashingEffect.cpp
index b6dbbd6e0ed19f877ca6c3c5b391e7334fe0923d..4493d37916683aa1e564c7810b72b993f5b62a60 100644
--- a/src/gpu/effects/GrDashingEffect.cpp
+++ b/src/gpu/effects/GrDashingEffect.cpp
@@ -1001,7 +1001,7 @@ GrGeometryProcessor* DashingCircleEffect::TestCreate(SkRandom* random,
                                                      GrTexture*[]) {
     DashAAMode aaMode = static_cast<DashAAMode>(random->nextULessThan(kDashAAModeCount));
     return DashingCircleEffect::Create(GrRandomColor(random),
-                                      aaMode, GrProcessorUnitTest::TestMatrix(random));
+                                      aaMode, GrTest::TestMatrix(random));
 }
 
 //////////////////////////////////////////////////////////////////////////////
@@ -1260,7 +1260,7 @@ GrGeometryProcessor* DashingLineEffect::TestCreate(SkRandom* random,
                                                    GrTexture*[]) {
     DashAAMode aaMode = static_cast<DashAAMode>(random->nextULessThan(kDashAAModeCount));
     return DashingLineEffect::Create(GrRandomColor(random),
-                                     aaMode, GrProcessorUnitTest::TestMatrix(random));
+                                     aaMode, GrTest::TestMatrix(random));
 }
 
 //////////////////////////////////////////////////////////////////////////////