[Android]: Don't omit the frame pointer on Arm64.

[Android]: Don't omit the frame pointer on Arm64.

If we omit the frame pointer on Arm64 there is no way for
breakpad to correctly symbolize stack traces which contain
stack frames for which we don't have CFI information (e.g.,
system libraries like libc.so).  This is because the Arm64
ABI does not specify where a frame pointer should be in a
stack frame, so, without CFI information, there is no way 
to calculate the start of the caller's frame if the caller
omits the frame pointer.

More details are on the bug.

BUG=391706
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=282370

[rmcilroy, 2014-07-10 13:58:43]

Primiano, could you please take a look, thanks.

[Primiano Tucci (use gerrit), 2014-07-10 14:44:20]

LGTM.
Just please fix the CL description.
I think the first line should be <= 72 chars
Also, I'd add some more context (about the vomitous aarch64 abi) in the commit
message.

Note: there seem to be some other -fomit-frame-pointer in skia. Not sure if you
need that as well.

[rmcilroy, 2014-07-10 15:37:36]

On 2014/07/10 14:44:20, Primiano Tucci wrote:
> LGTM.
> Just please fix the CL description.
> I think the first line should be <= 72 chars
> Also, I'd add some more context (about the vomitous aarch64 abi) in the commit
> message.
> 
> Note: there seem to be some other -fomit-frame-pointer in skia. Not sure if
you
> need that as well.

Updated description, and verified that the -fomit-frame-pointer in skia and V8
are either architecture specific (so don't apply to arm64 anyway) or are only
used when building the standalone skia / v8 binaries, not when building Chrome.

[rmcilroy, 2014-07-10 15:37:39]

The CQ bit was checked by rmcilroy@chromium.org

[commit-bot: I haz the power, 2014-07-10 15:39:14]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/rmcilroy@chromium.org/381923002/1

[commit-bot: I haz the power, 2014-07-10 17:37:42]

Change committed as 282370