run-perf-tests --chromium-android --profile should show symbols for the kernel
https://bugs.webkit.org/show_bug.cgi?id=106498

Reviewed by Adam Barth.

Turns out this was easy, once I finally read the output from "perf report".
It appears there may be a bug in "perf record" on android, as it complains
about not being able to read from /proc/kallsyms even when
/proc/sys/kernel/kptr_restrict is 0.  For now I've not bothered
to keep /proc/sys/kernel/kptr_restrict as 0 during the actual record
but rather just flip it to 0 long enough to grab the /proc/kallsyms
and then flip it back to whatever the device had.

/proc/sys/kernel/kptr_restrict controls what /proc/kallsyms returns
on Linux.  /proc/kallsyms contains a mapping of kernel addresses
to symbol names.  Its world-readable, but will return all 0s if you
don't have permission to see the kernel symbols.  kptr_restrict
supports values 0, 1, 2.  Where 0 means "everyone can see the real symbols"
1 is only a specific group, and 2 is "no one, not even root".
By default kptr_restrict is 2 on Android it seems.
More kptr_restrict docs: http://lwn.net/Articles/420403/

I also took this opportunity to clean up how the perf record command
was built for use/display in AndroidPerf.profile_after_exit and
change to always using long-form names for the arguments (to hopefully help readability).

* Scripts/webkitpy/layout_tests/port/chromium_android.py:
(AndroidPerf.__init__):
(profile_after_exit):
(ChromiumAndroidDriver.__init__):
(ChromiumAndroidDriver._update_kallsyms_cache):
* Scripts/webkitpy/layout_tests/port/chromium_android_unittest.py:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@139263 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Dont use a node reference after appending to the graph.
https://bugs.webkit.org/show_bug.cgi?id=103305
<rdar://problem/12753096>

Reviewed by Mark Hahnenberg.

* dfg/DFGArgumentsSimplificationPhase.cpp:
(JSC::DFG::ArgumentsSimplificationPhase::run):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@139264 268f45cc-cd09-0410-ab3c-d52691b4dbfc