Revert of Make RenderProcessHost/RenderThread use MojoChildConnection/MojoShellConnection

Revert of Make RenderProcessHost/RenderThread use MojoChildConnection/MojoShellConnection (patchset #5 id:80001 of https://codereview.chromium.org/2100693002/ )

Reason for revert:
Speculatively reverting because this may have broken Dr. Memory bots.

First breaking build:
https://build.chromium.org/p/chromium.memory.fyi/builders/Windows%20Unit%20%28DrMemory%20full%29%20%282%29/builds/11065

Bot:
https://build.chromium.org/p/chromium.memory.fyi/builders/Windows%20Unit%20(DrMemory%20full)%20(2)

Original issue's description:
> Make RenderProcessHost/RenderThread use MojoChildConnection/MojoShellConnection
> 
> Extracted from: https://codereview.chromium.org/2096643002/
> 
> TBR=rockot@chromium.org
> BUG=
> 
> Committed: https://crrev.com/b4e2536de302ecbc29ad7a40fc124e15e7c74e77
> Cr-Commit-Position: refs/heads/master@{#402225}

TBR=rockot@chromium.org,ben@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=

[tommycli, 2016-06-29 19:38:13]

The CQ bit was checked by tommycli@chromium.org

[tommycli, 2016-06-29 19:38:14]

Created Revert of Make RenderProcessHost/RenderThread use
MojoChildConnection/MojoShellConnection

[commit-bot: I haz the power, 2016-06-29 19:39:09]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-06-29 19:47:26]

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

[commit-bot: I haz the power, 2016-06-29 19:47:27]

Try jobs failed on following builders:
  android_arm64_dbg_recipe on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/android_arm6...)
  android_clang_dbg_recipe on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/android_clan...)
  android_compile_dbg on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/android_comp...)
  cast_shell_android on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/cast_shell_a...)
  linux_android_rel_ng on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)
  cast_shell_linux on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/cast_shell_linu...)
  chromeos_amd64-generic_chromium_compile_only_ng on
master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/chromeos_amd64-...)
  chromeos_daisy_chromium_compile_only_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/chromeos_daisy_...)
  chromeos_x86-generic_chromium_compile_only_ng on
master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/chromeos_x86-ge...)
  chromium_presubmit on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)
  linux_chromium_asan_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  linux_chromium_chromeos_compile_dbg_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  linux_chromium_chromeos_ozone_rel_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  linux_chromium_chromeos_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  linux_chromium_clobber_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  linux_chromium_compile_dbg_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  linux_chromium_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  ios-device on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device/builds...)
  ios-device-gn on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device-gn/bui...)
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)
  ios-simulator-gn on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator-gn/...)
  mac_chromium_compile_dbg_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_comp...)
  mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)
  win_chromium_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_...)
  win_clang on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_clang/builds/...)

[Ken Rockot(use gerrit already), 2016-06-29 19:48:15]

On 2016/06/29 at 19:39:09, commit-bot wrote:
> CQ is trying da patch. Follow status at
>  
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

It's going to be very hard to revert this as several large dependent CLs have
landed since

[Ken Rockot(use gerrit already), 2016-06-29 19:48:40]

On 2016/06/29 at 19:48:15, Ken Rockot wrote:
> On 2016/06/29 at 19:39:09, commit-bot wrote:
> > CQ is trying da patch. Follow status at
> >  
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...
> 
> It's going to be very hard to revert this as several large dependent CLs have
landed since

Fix is WIP

[tommycli, 2016-06-29 20:32:04]

On 2016/06/29 19:48:40, Ken Rockot wrote:
> On 2016/06/29 at 19:48:15, Ken Rockot wrote:
> > On 2016/06/29 at 19:39:09, commit-bot wrote:
> > > CQ is trying da patch. Follow status at
> > >  
>
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...
> > 
> > It's going to be very hard to revert this as several large dependent CLs
have
> landed since
> 
> Fix is WIP

Sounds good. Feel free to msg me once the fix is ready.