Remove unused (by clients) SkUnitMapper (https://codereview.chromium.org/283273002/)

This reverts commit dd50c83b5b34dab3a077741861b50ed1f2bc6b8f.

BUG=skia:
R=scroggo@google.com

Author: reed@google.com

Review URL: https://codereview.chromium.org/288343009

git-svn-id: http://skia.googlecode.com/svn/trunk@14830 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/DeferredCanvasTest.cpp b/tests/DeferredCanvasTest.cpp
index a5a763a..9ffb790 100644
--- a/tests/DeferredCanvasTest.cpp
+++ b/tests/DeferredCanvasTest.cpp
@@ -359,7 +359,7 @@
         const SkColor colors[2] = {SK_ColorWHITE, SK_ColorWHITE};
         const SkScalar pos[2] = {0, SK_Scalar1};
         SkShader* shader = SkGradientShader::CreateTwoPointConical(
-            pt1, r1, pt2, r2, colors, pos, 2, SkShader::kClamp_TileMode, NULL);
+            pt1, r1, pt2, r2, colors, pos, 2, SkShader::kClamp_TileMode);
         paint.setShader(shader)->unref();
         canvas->drawRect(fullRect, paint);
         REPORTER_ASSERT(reporter, !canvas->isFreshFrame());