Add missing null-checks.

Add missing null-checks.

These null-checks were inadvertedly removed during this
refactoring:
https://codereview.chromium.org/481803004/

getWebContents() can return null after destruction
so we need to null-check before use.

BUG=415666
Committed: https://crrev.com/c2401a37a0ba385317e71cb430356458328a12df
Cr-Commit-Position: refs/heads/master@{#297795}

[Ignacio Solla, 2014-09-30 10:15:19]

igsolla@chromium.org changed reviewers:
+ boliu@chromium.org, tedchoc@chromium.org

[Ignacio Solla, 2014-09-30 10:15:19]

boliu@chromium.org: Please review changes in android_webview/

tedchoc@chromium.org: Please review content/ and chrome/

[boliu, 2014-09-30 16:53:01]

On 2014/09/30 10:15:19, Ignacio Solla wrote:
> mailto:boliu@chromium.org: Please review changes in android_webview/

lgtm

> 
> mailto:tedchoc@chromium.org: Please review content/ and chrome/

Chrome shouldn't have webview's problem that the embedding app is written by
someone else, the code is defensive. The general trend there shouldn't be to add
null checks, but make sure the code never calls into content once destroy is
called, and then add DCHECKS/asserts.

But I'll let Ted review the specifics there :)

[Ted C, 2014-10-01 23:24:49]

I don't think any of these checks are necessary (outside of the aw folder).

As Bo stated, these would all represent logic bugs if we add null checks.

https://codereview.chromium.org/615883003/diff/20001/chrome/android/java/src/...
File chrome/android/java/src/org/chromium/chrome/browser/Tab.java (right):

https://codereview.chromium.org/615883003/diff/20001/chrome/android/java/src/...
chrome/android/java/src/org/chromium/chrome/browser/Tab.java:217: if
(getWebContents() != null)
This shouldn't happen.  This call only comes from the WebContentsDelegate and if
that happens getWebContents should never be null.

https://codereview.chromium.org/615883003/diff/20001/chrome/android/java/src/...
File
chrome/android/java/src/org/chromium/chrome/browser/banners/AppBannerManager.java
(right):

https://codereview.chromium.org/615883003/diff/20001/chrome/android/java/src/...
chrome/android/java/src/org/chromium/chrome/browser/banners/AppBannerManager.java:115:
if (mTab.getWebContents() != null)
these shouldn't be needed either

And although this file isn't consistent, we should be requring braces on all
conditionals (unless the statement and conditional can all fit on the same line)

https://codereview.chromium.org/615883003/diff/20001/content/public/android/j...
File
content/public/android/java/src/org/chromium/content/browser/accessibility/JellyBeanAccessibilityInjector.java
(right):

https://codereview.chromium.org/615883003/diff/20001/content/public/android/j...
content/public/android/java/src/org/chromium/content/browser/accessibility/JellyBeanAccessibilityInjector.java:73:
if (!accessibilityIsAvailable() || !mContentViewCore.isAlive() ||
The isAlive check should be sufficient for this and the check below shouldn't be
needed either.

https://codereview.chromium.org/615883003/diff/20001/content/public/android/j...
content/public/android/java/src/org/chromium/content/browser/accessibility/JellyBeanAccessibilityInjector.java:82:
mContentViewCore.getWebContents().showImeIfNeeded();
this is not the correct style per previous comment

[Ignacio Solla, 2014-10-02 09:11:14]

I have reverted all the null-checks outside android_webview. 

The intent of this patch was just to revert to a known good state where perhaps
we had more null-checks that we needed without doing an audit of every check.
Ted believes that those null-checks are not needed so I have removed them. If an
audit is needed I guess the author of https://codereview.chromium.org/481803004/
should help with that.

https://codereview.chromium.org/615883003/diff/20001/chrome/android/java/src/...
File chrome/android/java/src/org/chromium/chrome/browser/Tab.java (right):

https://codereview.chromium.org/615883003/diff/20001/chrome/android/java/src/...
chrome/android/java/src/org/chromium/chrome/browser/Tab.java:217: if
(getWebContents() != null)
On 2014/10/01 23:24:49, Ted C wrote:
> This shouldn't happen.  This call only comes from the WebContentsDelegate and
if
> that happens getWebContents should never be null.

Removed.

https://codereview.chromium.org/615883003/diff/20001/chrome/android/java/src/...
File
chrome/android/java/src/org/chromium/chrome/browser/banners/AppBannerManager.java
(right):

https://codereview.chromium.org/615883003/diff/20001/chrome/android/java/src/...
chrome/android/java/src/org/chromium/chrome/browser/banners/AppBannerManager.java:115:
if (mTab.getWebContents() != null)
On 2014/10/01 23:24:49, Ted C wrote:
> these shouldn't be needed either
> 
> And although this file isn't consistent, we should be requring braces on all
> conditionals (unless the statement and conditional can all fit on the same
line)

Removed.

https://codereview.chromium.org/615883003/diff/20001/content/public/android/j...
File
content/public/android/java/src/org/chromium/content/browser/accessibility/JellyBeanAccessibilityInjector.java
(right):

https://codereview.chromium.org/615883003/diff/20001/content/public/android/j...
content/public/android/java/src/org/chromium/content/browser/accessibility/JellyBeanAccessibilityInjector.java:73:
if (!accessibilityIsAvailable() || !mContentViewCore.isAlive() ||
On 2014/10/01 23:24:49, Ted C wrote:
> The isAlive check should be sufficient for this and the check below shouldn't
be
> needed either.

Removed.

https://codereview.chromium.org/615883003/diff/20001/content/public/android/j...
content/public/android/java/src/org/chromium/content/browser/accessibility/JellyBeanAccessibilityInjector.java:82:
mContentViewCore.getWebContents().showImeIfNeeded();
On 2014/10/01 23:24:49, Ted C wrote:
> this is not the correct style per previous comment

Reverted.

[Ignacio Solla, 2014-10-02 09:12:07]

The CQ bit was checked by igsolla@chromium.org

[commit-bot: I haz the power, 2014-10-02 09:13:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/615883003/60001

[commit-bot: I haz the power, 2014-10-02 10:09:17]

Committed patchset #4 (id:60001) as 17f1da7d79f81c4c6a3e973f79c91f548ad1d85b

[commit-bot: I haz the power, 2014-10-02 10:10:24]

Patchset 4 (id:??) landed as
https://crrev.com/c2401a37a0ba385317e71cb430356458328a12df
Cr-Commit-Position: refs/heads/master@{#297795}