Revert of On Android, links inside headings should be announced as headings by TalkBack

Revert of On Android, links inside headings should be announced as headings by TalkBack (patchset #4 id:60001 of https://codereview.chromium.org/845663002/)

Reason for revert:
This caused content_browsertests to fail on the Android bots, e.g.:

http://build.chromium.org/p/chromium.linux/builders/Android%20Tests/builds/17857

C 1232.064s Main  [FAIL] DumpAccessibilityTreeTest.AccessibilityLinkInsideHeading:
C 1232.064s Main  [WARNING:dns_config_service_posix.cc(293)] Failed to read DnsConfig.
C 1232.065s Main  [ERROR:unix_domain_server_socket_posix.cc(106)] Not implemented reached in virtual int net::UnixDomainServerSocket::GetLocalAddress(net::IPEndPoint*) const
C 1232.065s Main  [WARNING:proxy_service.cc(899)] PAC support disabled because there is no system implementation
C 1232.065s Main  Testing: /storage/emulated/0/content/test/data/accessibility/html/link-inside-heading.html
C 1232.065s Main  ../../content/browser/accessibility/dump_accessibility_browsertest_base.cc:202: Failure
C 1232.065s Main  Value of: is_different
C 1232.065s Main    Actual: true
C 1232.065s Main  Expected: false
C 1232.065s Main  * Line Expected
C 1232.065s Main  - ---- --------
C 1232.065s Main       1 android.webkit.WebView focusable focused scrollable
C 1232.065s Main       2     android.view.View heading
C 1232.065s Main  *    3         android.view.View clickable focusable heading name='Link In Heading'
C 1232.065s Main       4 <-- End-of-file -->
C 1232.065s Main
C 1232.065s Main  Actual
C 1232.065s Main  ------
C 1232.065s Main  android.webkit.WebView focusable focused scrollable
C 1232.065s Main      android.view.View heading
C 1232.066s Main          android.view.View clickable focusable heading link name='Link In Heading'
C 1232.066s Main  <-- End-of-file -->

Original issue's description:
> On Android, links inside headings should be announced as headings by TalkBack
>
> BUG=446216
>
> Committed: https://crrev.com/68e8e33eff3a16754b9a99681d0586041436bb62
> Cr-Commit-Position: refs/heads/master@{#312086}

TBR=dmazzoni@chromium.org,aboxhall@chromium.org,ramya.v@samsung.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=446216
Committed: https://crrev.com/4fe2125920ff2503f299d4a12e5d5b291139175b
Cr-Commit-Position: refs/heads/master@{#312102}

[bartfab (slow), 2015-01-19 12:49:02]

Created Revert of On Android, links inside headings should be announced as
headings by TalkBack

[commit-bot: I haz the power, 2015-01-19 12:50:00]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/862503002/1

[commit-bot: I haz the power, 2015-01-19 12:50:56]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-19 12:51:55]

Patchset 1 (id:??) landed as
https://crrev.com/4fe2125920ff2503f299d4a12e5d5b291139175b
Cr-Commit-Position: refs/heads/master@{#312102}