change SkDrawFilter::filter to return a bool, where false means don't-draw
Review URL: https://codereview.appspot.com/6851111

git-svn-id: http://skia.googlecode.com/svn/trunk@6551 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/samplecode/SampleLayers.cpp b/samplecode/SampleLayers.cpp
index 6d57c2a..cf6b009 100644
--- a/samplecode/SampleLayers.cpp
+++ b/samplecode/SampleLayers.cpp
@@ -125,11 +125,12 @@
 
 class RedFilter : public SkDrawFilter {
 public:
-    virtual void filter(SkPaint* p, SkDrawFilter::Type) SK_OVERRIDE {
+    virtual bool filter(SkPaint* p, SkDrawFilter::Type) SK_OVERRIDE {
         fColor = p->getColor();
         if (fColor == SK_ColorRED) {
             p->setColor(SK_ColorGREEN);
         }
+        return true;
     }
 
 private: