Fixed issue where large blur radii

would blur less than smaller blur radii

Changed SkImageFilter blur creation to include
SkTileMode::kClamp parameter to use edge pixels
for blur kernels that are larger than the source

Fixes: 167493483
Test: Added test to CTS ShaderTest
Change-Id: Ibbe1e0dfaf46413fcae665620fd154b9bf9897c9

libs/hwui/shader/BlurShader.cpp

@@ -26,7 +26,9 @@ BlurShader::BlurShader(float radiusX, float radiusY, Shader* inputShader, const
             SkImageFilters::Blur(
                     Blur::convertRadiusToSigma(radiusX),
                     Blur::convertRadiusToSigma(radiusY),
-                    inputShader ? inputShader->asSkImageFilter() : nullptr)
+                    SkTileMode::kClamp,
+                    inputShader ? inputShader->asSkImageFilter() : nullptr,
+                    nullptr)
             ) { }
 
 sk_sp<SkImageFilter> BlurShader::makeSkImageFilter() {