Fixed bad bitmap size crashes

There were 2 issues :
1 ) If the size of an SkBitmap's underlying SkPixelRef's alocated memory is too small to fit the bitmap, then the deserialization will now check this and set an error appropriately.
2 ) If a device fails to allocate its pixels, the device will be deleted and NULL will be returned to avoid attempting to draw on a bad device.

BUG=
R=senorblanco@chromium.org, reed@google.com, sugoi@google.com, halcanary@google.com, mtklein@google.com

Author: sugoi@chromium.org

Review URL: https://codereview.chromium.org/92793002

git-svn-id: http://skia.googlecode.com/svn/trunk@12484 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/effects/SkTileImageFilter.cpp b/src/effects/SkTileImageFilter.cpp
index ccca4ff..7d3b72f 100644
--- a/src/effects/SkTileImageFilter.cpp
+++ b/src/effects/SkTileImageFilter.cpp
@@ -38,6 +38,9 @@
     }
 
     SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(w, h));
+    if (NULL == device.get()) {
+        return false;
+    }
     SkIRect bounds;
     source.getBounds(&bounds);
     SkCanvas canvas(device);