GN: Update heap stubs for android

GN: Update heap stubs for android

On non-intel (aka non x86/x64) we can compile the assembly stubs as a
source_set and not use yasm.

R=brettw@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=181529

[jamesr, 2014-09-05 00:58:52]

Oh whoops, these were already in Source/platform/heap/.  Huh, wonder why it
isn't using yasm for the intel platforms...

[jamesr, 2014-09-05 00:59:31]

Oh, the one in Source/platform/heap/ probably does nothing on x86/x64 since the
.S file won't be compiled there.  Annoying...

[jamesr, 2014-09-05 01:01:52]

https://codereview.chromium.org/541933003/diff/20001/Source/platform/heap/BUI...
File Source/platform/heap/BUILD.gn (left):

https://codereview.chromium.org/541933003/diff/20001/Source/platform/heap/BUI...
Source/platform/heap/BUILD.gn:19: if (cpu_arch == "x86" || cpu_arch == "x64") {
i don't think these did the right thing beforehand.  on intel, the ".asm" file
would be ignored.  On other platforms, the stubs would compile but this target
doesn't set the correct defines for the stubs.  Since there's already a yasm
target in the parent I think the right thing is to just delete this (or move the
whole mess in Source/platform/BUILD.gn up to this directory, or move it to
Source/platform/heap/asm).  WDYT?

[jamesr, 2014-09-05 17:52:34]

On further thought I think hiding all this in Source/platform/heap/asm/BUILD.gn
makes even more sense.  It's a bit ugly but it's very isolated.

[brettw, 2014-09-05 19:48:53]

lgtm

[jamesr, 2014-09-05 19:49:20]

The CQ bit was checked by jamesr@chromium.org

[commit-bot: I haz the power, 2014-09-05 19:50:09]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jamesr@chromium.org/541933003/60001

[commit-bot: I haz the power, 2014-09-06 07:48:07]

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

[commit-bot: I haz the power, 2014-09-06 07:48:08]

Exceeded time limit waiting for builds to trigger.

[jamesr, 2014-09-07 22:23:13]

The CQ bit was checked by jamesr@chromium.org

[commit-bot: I haz the power, 2014-09-07 22:24:13]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jamesr@chromium.org/541933003/60001

[commit-bot: I haz the power, 2014-09-07 22:24:39]

Committed patchset #4 (id:60001) as 181529