Fixed bad bitmap size crashes

src/effects/SkMorphologyImageFilter.cpp

Index: src/effects/SkMorphologyImageFilter.cpp
diff --git a/src/effects/SkMorphologyImageFilter.cpp b/src/effects/SkMorphologyImageFilter.cpp
index 3f2f98557afc9d89e8765acc1e86eb0f5e80deb5..0d00c359d85656694559ad25690dd10d0588f873 100644
--- a/src/effects/SkMorphologyImageFilter.cpp
+++ b/src/effects/SkMorphologyImageFilter.cpp
@@ -188,6 +188,9 @@ bool SkErodeImageFilter::onFilterImage(Proxy* proxy,
 
     dst->setConfig(src.config(), bounds.width(), bounds.height());
     dst->allocPixels();
+    if (!dst->getPixels()) {
+        return false;
+    }
 
     int width = radius().width();
     int height = radius().height();
@@ -247,6 +250,9 @@ bool SkDilateImageFilter::onFilterImage(Proxy* proxy,
 
     dst->setConfig(src.config(), bounds.width(), bounds.height());
     dst->allocPixels();
+    if (!dst->getPixels()) {
+        return false;
+    }
 
     int width = radius().width();
     int height = radius().height();