Don't assume WebContents has a LastCommittedEntry when setting zoom.

Don't assume WebContents has a LastCommittedEntry when setting zoom.

In HostZoomMapImpl::SetZoomLevelForWebContents() we currently make the
assumption that the WebContents passed in will always have a non-null
last-committed navigation entry, but this leads to failures on the
fuzzing tests. This CL removes that assumption, and ignores attempts to
set zoom if no such entry exists.

BUG=382320
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=276040

[wjmaclean, 2014-06-09 17:35:59]

https://codereview.chromium.org/320863002/diff/1/content/browser/host_zoom_ma...
File content/browser/host_zoom_map_impl.cc (right):

https://codereview.chromium.org/320863002/diff/1/content/browser/host_zoom_ma...
content/browser/host_zoom_map_impl.cc:254: url = entry->GetURL();
Actually, this should be 

GURL url = ...

No need to declare it outside the if()

[Peter Kasting, 2014-06-09 18:17:57]

LGTM

https://codereview.chromium.org/320863002/diff/1/content/browser/host_zoom_ma...
File content/browser/host_zoom_map_impl.cc (right):

https://codereview.chromium.org/320863002/diff/1/content/browser/host_zoom_ma...
content/browser/host_zoom_map_impl.cc:245: } else {
Tiny nit: For parallel structure with the function above, you might want to use
an early-return instead of this "else".  Up to you.

https://codereview.chromium.org/320863002/diff/1/content/browser/host_zoom_ma...
content/browser/host_zoom_map_impl.cc:253: if (entry) {
Nit: Add a comment about why this can be NULL.  Ideally, the comments both here
and above actually give the reader some detail about the codepath that leads to
this, rather than just saying something like "it's possible there is no entry
yet".

[jam, 2014-06-09 20:00:21]

lgtm

[wjmaclean, 2014-06-09 20:20:28]

The CQ bit was checked by wjmaclean@chromium.org

[commit-bot: I haz the power, 2014-06-09 20:29:26]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/wjmaclean@chromium.org/320863002/20001

[commit-bot: I haz the power, 2014-06-10 09:00:30]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  android_clang_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/android_clang_dbg/bui...)
  linux_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_rel/bu...)

[commit-bot: I haz the power, 2014-06-10 12:13:17]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-06-10 12:13:18]

Try jobs failed on following builders:
  android_clang_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/android_clang_dbg/bui...)

[wjmaclean, 2014-06-10 12:29:15]

The CQ bit was checked by wjmaclean@chromium.org

[commit-bot: I haz the power, 2014-06-10 12:36:38]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/wjmaclean@chromium.org/320863002/20001

[commit-bot: I haz the power, 2014-06-10 14:41:04]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  android_clang_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/android_clang_dbg/bui...)

[commit-bot: I haz the power, 2014-06-10 15:47:45]

Change committed as 276040