check for null-device pixels in onWritePixels, so we don't crash

gm/stroketext.cpp

Index: gm/stroketext.cpp
diff --git a/gm/stroketext.cpp b/gm/stroketext.cpp
index 1791fea528ca3f4a1bf4cf3c7e1f4f6fd134f793..b9d56f10e470b167e9df738e3d3a671209a0d073 100644
--- a/gm/stroketext.cpp
+++ b/gm/stroketext.cpp
@@ -8,6 +8,21 @@
 #include "gm.h"
 #include "SkCanvas.h"
 
+static void test_nulldev(SkCanvas* canvas) {

[bsalomon, 2014/03/14 14:03:45]

should this be in a unit test?

+    SkBitmap bm;
+    bm.setConfig(SkBitmap::kARGB_8888_Config, 30, 30);
+    // notice: no pixels mom! be sure we don't crash
+    // https://code.google.com/p/chromium/issues/detail?id=352616
+    SkCanvas c(bm);
+
+    SkBitmap src;
+    src.allocN32Pixels(10, 10);
+    src.eraseColor(SK_ColorRED);
+
+    // ensure we don't crash
+    c.writePixels(src, 0, 0);
+}
+
 static void draw_text_stroked(SkCanvas* canvas, const SkPaint& paint) {
     SkPaint p(paint);
     SkPoint loc = { 20, 450 };
@@ -44,6 +59,7 @@ protected:
     }
 
     virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
+        if (true) { test_nulldev(canvas); }
         SkPaint paint;
         paint.setAntiAlias(true);