Revert of Turn ChannelMojo on Mac and Linux

Revert of Turn ChannelMojo on Mac and Linux (patchset #5 id:80001 of https://codereview.chromium.org/664413003/)

Reason for revert:
Got a perf regression report. Reverting.


Original issue's description:
> Turn ChannelMojo on Mac and Linux
> 
> I don't see any page_cycler regression locally so I'll try
> to enable this on trunk as the nex step.
> This change doesn't turn this on Windows to keep the scope of
> possible trouble small.
> 
> BUG=377980
> R=viettrungluu@chromium.org, darin@chromium.org
> 
> Committed: https://crrev.com/45d3cbd888ea1f20145e0f1451a7920a62a6653d
> Cr-Commit-Position: refs/heads/master@{#304949}

TBR=darin@chromium.org,viettrungluu@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=377980

[Hajime Morrita, 2014-11-26 17:42:41]

Created Revert of Turn ChannelMojo on Mac and Linux

[commit-bot: I haz the power, 2014-11-26 17:43:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/760753005/1

[commit-bot: I haz the power, 2014-11-26 17:43:43]

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

[commit-bot: I haz the power, 2014-11-26 17:43:46]

Failed to apply patch for ipc/mojo/ipc_channel_mojo.cc:
While running git apply --index -3 -p1;
  error: patch failed: ipc/mojo/ipc_channel_mojo.cc:175
  error: repository lacks the necessary blob to fall back on 3-way merge.
  error: ipc/mojo/ipc_channel_mojo.cc: patch does not apply

Patch:       ipc/mojo/ipc_channel_mojo.cc
Index: ipc/mojo/ipc_channel_mojo.cc
diff --git a/ipc/mojo/ipc_channel_mojo.cc b/ipc/mojo/ipc_channel_mojo.cc
index
45cdc1aafd70f2d3da723663e84c14b5e4fab690..4051bb5c21a87c3ea49811a7f30cfaeea124018f
100644
--- a/ipc/mojo/ipc_channel_mojo.cc
+++ b/ipc/mojo/ipc_channel_mojo.cc
@@ -175,15 +175,8 @@
 
 // static
 bool ChannelMojo::ShouldBeUsed() {
-  // Being conservative, this is currently enabled only on Mac and
-  // Linux even though this should work on all platforms.
-  // TODO(morrita): Turn this on all platform and kill
-  // --enable-renderer-mojo-channel
-#if defined(OS_POSIX) && !defined(OS_ANDROID)
-  return true;
-#else
+  // TODO(morrita): Turn this on for a set of platforms.
   return false;
-#endif
 }
 
 // static

[commit-bot: I haz the power, 2014-11-26 17:43:49]

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