Mac gpu: on gpu<->nongpu transitions, make sure to not show uninitialized memory

Mac gpu: on gpu<->nongpu transitions, make sure to not show uninitialized memory

Two fixes:
1. Wait for the software backing store to paint before hiding the gpu view (this was http://codereview.chromium.org/4030005 , now changed to address the review feedback)
2. Disable screen updates until window flush when hiding the gpu view

BUG=57645
TEST=Mouse over sticky notes at http://nettuts.s3.amazonaws.com/771_sticky/step5.html , shouldn't flicker. Zoom in and out on maps.google.com, shouldn't flicker.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=64821

[stuartmorgan, 2010-11-02 16:46:49]

http://codereview.chromium.org/4148004/diff/13001/14005
File chrome/browser/renderer_host/render_widget_host_view_mac.mm (right):

http://codereview.chromium.org/4148004/diff/13001/14005#newcode722
chrome/browser/renderer_host/render_widget_host_view_mac.mm:722: // hiding until
-callSetNeedsDisplayInRect runs.
I'm confused; the comment says to delay, but the code right below it is doing
just what cSNDIR: is doing.

[Nico, 2010-11-02 18:43:53]

http://codereview.chromium.org/4148004/diff/13001/14005
File chrome/browser/renderer_host/render_widget_host_view_mac.mm (right):

http://codereview.chromium.org/4148004/diff/13001/14005#newcode722
chrome/browser/renderer_host/render_widget_host_view_mac.mm:722: // hiding until
-callSetNeedsDisplayInRect runs.
On 2010/11/02 16:46:49, stuartmorgan wrote:
> I'm confused; the comment says to delay, but the code right below it is doing
> just what cSNDIR: is doing.

Oh yes, this is worded very confusingly. It'd be slightly better to put the
comment above the if. What I'm trying to say is

"if |about_to_validate_and_paint_| is set, then -drawRect: is on the stack and
it's not allowed to call -setHidden on the accelerated view. In that case,
-callSetNeedsDisplayInRect: will hide it later. If
|about_to_validate_and_paint_| is not set, do it now."

Do you have a good idea how to put that? Should I replace the comment with what
I've just written?

[Nico, 2010-11-02 20:46:12]

Thanks.

http://codereview.chromium.org/4148004/diff/13001/14005
File chrome/browser/renderer_host/render_widget_host_view_mac.mm (right):

http://codereview.chromium.org/4148004/diff/13001/14005#newcode1514
chrome/browser/renderer_host/render_widget_host_view_mac.mm:1514: }
On 2010/11/02 20:20:47, stuartmorgan wrote:
> Since there aret two copies of this code, and this copy is doing nothing but
> interacting with RWHV members and methods, add a helper method on RWHV and
make
> both sites call it.

Done.

[stuartmorgan, 2010-11-02 20:54:57]

LGTM with nits.

http://codereview.chromium.org/4148004/diff/24001/25004
File chrome/browser/renderer_host/render_widget_host_view_mac.h (right):

http://codereview.chromium.org/4148004/diff/24001/25004#newcode272
chrome/browser/renderer_host/render_widget_host_view_mac.h:272: // hidden until
the software backing store has been updated. This method checks
80 chars

http://codereview.chromium.org/4148004/diff/24001/25005
File chrome/browser/renderer_host/render_widget_host_view_mac.mm (right):

http://codereview.chromium.org/4148004/diff/24001/25005#newcode979
chrome/browser/renderer_host/render_widget_host_view_mac.mm:979: void
RenderWidgetHostViewMac::DelayedHideGpuViewIfNecessary() {
How about HandleDelayedGpuViewHiding() or something similar? The current name
implies that it does something on a delay.

[Nico, 2010-11-02 20:58:42]

Thanks!

http://codereview.chromium.org/4148004/diff/24001/25004
File chrome/browser/renderer_host/render_widget_host_view_mac.h (right):

http://codereview.chromium.org/4148004/diff/24001/25004#newcode272
chrome/browser/renderer_host/render_widget_host_view_mac.h:272: // hidden until
the software backing store has been updated. This method checks
On 2010/11/02 20:54:58, stuartmorgan wrote:
> 80 chars

Done.

http://codereview.chromium.org/4148004/diff/24001/25005
File chrome/browser/renderer_host/render_widget_host_view_mac.mm (right):

http://codereview.chromium.org/4148004/diff/24001/25005#newcode979
chrome/browser/renderer_host/render_widget_host_view_mac.mm:979: void
RenderWidgetHostViewMac::DelayedHideGpuViewIfNecessary() {
On 2010/11/02 20:54:58, stuartmorgan wrote:
> How about HandleDelayedGpuViewHiding() or something similar? The current name
> implies that it does something on a delay.

Done.