Clear SkBitmap used to draw DragImage.

Clear SkBitmap used to draw DragImage.

SkBitmap::allocN32Pixels does not initialize the pixel memory, and we
may not draw to all of it (if, for example, an image decode fails,
nothing will be drawn).

BUG=450389
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=189585

[jbroman, 2015-02-05 17:58:20]

jbroman@chromium.org changed reviewers:
+ fmalita@chromium.org, schenney@chromium.org

[jbroman, 2015-02-05 17:58:20]

I think there are a few other places we neglect to do this (I wish it were
automatic, but alas...), but they're mostly in tests and I want to keep this CL
small so I can safely merge it into beta (and possibly stable).

[Stephen Chennney, 2015-02-05 17:59:54]

Can you give me access to the bug?

[f(malita), 2015-02-05 18:02:34]

lgtm

https://codereview.chromium.org/901223002/diff/1/Source/platform/DragImage.cpp
File Source/platform/DragImage.cpp (right):

https://codereview.chromium.org/901223002/diff/1/Source/platform/DragImage.cp...
Source/platform/DragImage.cpp:100: canvas.clear(SK_ColorTRANSPARENT);
Nit: this is technically subject to the (default) clip, so just for clarity I
would call skBitmap.eraseColor() instead.

[jbroman, 2015-02-05 18:05:14]

New patchsets have been uploaded after l-g-t-m from fmalita@chromium.org

[jbroman, 2015-02-05 18:07:57]

https://codereview.chromium.org/901223002/diff/1/Source/platform/DragImage.cpp
File Source/platform/DragImage.cpp (right):

https://codereview.chromium.org/901223002/diff/1/Source/platform/DragImage.cp...
Source/platform/DragImage.cpp:100: canvas.clear(SK_ColorTRANSPARENT);
On 2015/02/05 18:02:33, f(malita) wrote:
> Nit: this is technically subject to the (default) clip, so just for clarity I
> would call skBitmap.eraseColor() instead.

Done. I was waffling between the two, and I'm perfectly happy eraseColor.

[jbroman, 2015-02-05 18:30:01]

The CQ bit was checked by jbroman@chromium.org

[commit-bot: I haz the power, 2015-02-05 18:30:33]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/901223002/20001

[commit-bot: I haz the power, 2015-02-05 20:57:09]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=189585