<webview>: Allocate the view instance ID from the WebView shim

<webview>: Allocate the view instance ID from the WebView shim

This CL allocates a creates unique instance id for each
<webview> in an embedder RenderView/shim instead of in BrowserPlugin. In a subsequent CL, this will permit
usage of the WebRequest API prior to attachment to the DOM.

This CL also fixes a potential crash on edit commands if the instance ID passed did not exist: Perhaps open two <webview> apps and then close the first one, then send edit commands to the second one.

BUG=178663
Test=WebViewTest.*, WebViewInteractiveTest.*
TBR=cdn@chromium.org for deleted field in browser_plugin_messages.h

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=215807

[lazyboy, 2013-08-05 16:21:15]

lgtm

Mostly comment on the CL description:

"This CL allocates a unique instance ID per <webview> per RenderView" -> if I
understand this correctly, clearer would be 'creates unique instance id for each
<webview> in an embedder RenderView/shim'

"This CL also fixes a potential crash on edit commands if the instance ID passed
did not exist: Perhaps open two <webview> apps and then close the first one,
then send edit commands to the second one."
This is speculative, right? Hopefully this is the case.

[Fady Samuel, 2013-08-05 18:36:00]

On 2013/08/05 16:21:15, lazyboy wrote:
> lgtm
> 
> Mostly comment on the CL description:
> 
> "This CL allocates a unique instance ID per <webview> per RenderView" -> if I
> understand this correctly, clearer would be 'creates unique instance id for
each
> <webview> in an embedder RenderView/shim'
> 

Done.


> "This CL also fixes a potential crash on edit commands if the instance ID
passed
> did not exist: Perhaps open two <webview> apps and then close the first one,
> then send edit commands to the second one."
> This is speculative, right? Hopefully this is the case.

Yes it's speculative. I've been trying to write a test that triggers the crash
but I'm not there yet.

I'll try to write one in parallel with landing this code.

[Fady Samuel, 2013-08-05 18:37:14]

+jam@ for small content/public/* change

[jam, 2013-08-05 19:50:09]

On 2013/08/05 18:37:14, Fady Samuel wrote:
> +jam@ for small content/public/* change

lgtm

[commit-bot: I haz the power, 2013-08-06 01:49:35]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/fsamuel@chromium.org/21930006/10001

[commit-bot: I haz the power, 2013-08-06 05:57:47]

Change committed as 215807