Valgrind is not a fan of uninitialized Src pixels.

bench/BitmapScaleBench.cpp

Index: bench/BitmapScaleBench.cpp
diff --git a/bench/BitmapScaleBench.cpp b/bench/BitmapScaleBench.cpp
index 2e8f72e03c2097e725de5304df8b258a4308e41a..e309d5162cd3154919f234866e44d38f9ed96b53 100644
--- a/bench/BitmapScaleBench.cpp
+++ b/bench/BitmapScaleBench.cpp
@@ -124,12 +124,12 @@ public:
     PixmapScalerBench(SkBitmapScaler::ResizeMethod method, const char suffix[]) : fMethod(method) {
         fName.printf("pixmapscaler_%s", suffix);
     }
-    
+
 protected:
     const char* onGetName() override {
         return fName.c_str();
     }
-    
+
     SkIPoint onGetSize() override { return{ 100, 100 }; }
 
     bool isSuitableFor(Backend backend) override {
@@ -138,9 +138,10 @@ protected:
 
     void onDelayedSetup() override {
         fSrc.allocN32Pixels(640, 480);
+        fSrc.eraseColor(SK_ColorWHITE);
         fDst.allocN32Pixels(300, 250);
     }
-    
+
     void onDraw(int loops, SkCanvas*) override {
         SkPixmap src, dst;
         fSrc.peekPixels(&src);