Cache auxiliary bitmap across draw frames

Cache auxiliary bitmap across draw frames

While this mode isn't intended to be used in anger, the slow down caused
by reallocating the temp bitmap every frame is very high even for a
development configuration.
Also add a bunch of useful tracing.

BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=202035

[boliu, 2013-05-23 02:52:13]

lgtm

https://codereview.chromium.org/15795002/diff/1/android_webview/native/java_b...
File android_webview/native/java_browser_view_renderer_helper.cc (right):

https://codereview.chromium.org/15795002/diff/1/android_webview/native/java_b...
android_webview/native/java_browser_view_renderer_helper.cc:26:
TRACE_EVENT0("android_webview", "RendererHelper::CreateBitmap");
nit: can log cache_result, and ideally also log whether it created a new bitmap
or reused one

[kaanb, 2013-05-23 16:56:11]

lgtm

https://codereview.chromium.org/15795002/diff/1/android_webview/browser/brows...
File android_webview/browser/browser_view_renderer_impl.cc (right):

https://codereview.chromium.org/15795002/diff/1/android_webview/browser/brows...
android_webview/browser/browser_view_renderer_impl.cc:423: env,
picture->width(), picture->height(), false));
Any reason we don't want to support it for CapturePicture?

https://codereview.chromium.org/15795002/diff/1/android_webview/java/src/org/...
File
android_webview/java/src/org/chromium/android_webview/JavaBrowserViewRendererHelper.java
(right):

https://codereview.chromium.org/15795002/diff/1/android_webview/java/src/org/...
android_webview/java/src/org/chromium/android_webview/JavaBrowserViewRendererHelper.java:37:
if (cacheResult) sCachedBitmap = new SoftReference<Bitmap>(result);
nit: it would be more readable if you break this statement into two lines.

[joth, 2013-05-23 20:23:14]

https://codereview.chromium.org/15795002/diff/1/android_webview/browser/brows...
File android_webview/browser/browser_view_renderer_impl.cc (right):

https://codereview.chromium.org/15795002/diff/1/android_webview/browser/brows...
android_webview/browser/browser_view_renderer_impl.cc:423: env,
picture->width(), picture->height(), false));
On 2013/05/23 16:56:11, kaanb wrote:
> Any reason we don't want to support it for CapturePicture?

(this whole file is being deleted soon, but for the other version of this...)
The SkPicture has a shallow ref to any bitmaps drawn, but the client may hold
onto the picture for a long time. so if we reuse the bitmap for different
purposes, we'll corrupt previously drawn pictures.
Added a comment to the other place to explain this.

https://codereview.chromium.org/15795002/diff/1/android_webview/java/src/org/...
File
android_webview/java/src/org/chromium/android_webview/JavaBrowserViewRendererHelper.java
(right):

https://codereview.chromium.org/15795002/diff/1/android_webview/java/src/org/...
android_webview/java/src/org/chromium/android_webview/JavaBrowserViewRendererHelper.java:37:
if (cacheResult) sCachedBitmap = new SoftReference<Bitmap>(result);
On 2013/05/23 16:56:11, kaanb wrote:
> nit: it would be more readable if you break this statement into two lines.

Done.

https://codereview.chromium.org/15795002/diff/1/android_webview/native/java_b...
File android_webview/native/java_browser_view_renderer_helper.cc (right):

https://codereview.chromium.org/15795002/diff/1/android_webview/native/java_b...
android_webview/native/java_browser_view_renderer_helper.cc:26:
TRACE_EVENT0("android_webview", "RendererHelper::CreateBitmap");
On 2013/05/23 02:52:13, boliu wrote:
> nit: can log cache_result,  and ideally also log whether it created a new
bitmap
> or reused one

Done (although it's mostly obvious in a trace from the relative timings)

[commit-bot: I haz the power, 2013-05-24 05:22:23]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/joth@chromium.org/15795002/8001

[commit-bot: I haz the power, 2013-05-24 09:42:24]

Change committed as 202035