Android: fix cpu_features for WebView build.

Android: fix cpu_features for WebView build.

The WebView build doesn't have third_party/android_tools/ndk with the
added gyp file, but the cpufeatures code has already been built as part
of the system. Introduce a .gypi that can be included to get the
appropriate dependency for the current build type.

BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=169026

[Torne, 2012-11-21 11:35:25]

This seems to work in the webview build from my testing, and the trybots are
running now to confirm it hasn't broken the regular build.

[mkosiba (inactive), 2012-11-21 11:46:39]

LGTM

CCing Armand

[joth, 2012-11-21 17:43:19]

thanks!

https://codereview.chromium.org/11417114/diff/1/build/android/cpufeatures.gypi
File build/android/cpufeatures.gypi (right):

https://codereview.chromium.org/11417114/diff/1/build/android/cpufeatures.gyp...
build/android/cpufeatures.gypi:18: }],
just to check - neither these set the include path. Do we get cpufeatures.h "for
free" from whatever NDK include path we happen to be using? If so there could be
a version mismatch between that, and the system built version of the static lib.
(?)

[wjia(left Chromium), 2012-11-21 18:39:40]

https://codereview.chromium.org/11417114/diff/1/build/android/cpufeatures.gypi
File build/android/cpufeatures.gypi (right):

https://codereview.chromium.org/11417114/diff/1/build/android/cpufeatures.gyp...
build/android/cpufeatures.gypi:18: }],
On 2012/11/21 17:43:20, joth wrote:
> just to check - neither these set the include path. Do we get cpufeatures.h
"for
> free" from whatever NDK include path we happen to be using? If so there could
be
> a version mismatch between that, and the system built version of the static
lib.
> (?)

For branch using '<(android_ndk_root)/android_tools_ndk.gyp:cpu_features', the
path to third_party/android_tools/ndk/sources/android/cpufeatures/cpufeatures.h
has been included in include path. And it uses
third_party/android_tools/ndk/sources/android/cpufeatures/cpufeatures.c to make
libcpu_features.a. refer to
http://git.chromium.org/gitweb/?p=android_tools.git;a=blob_plain;f=ndk/androi...
.

Please let me know if this could be a problem.

[navabi1, 2012-11-21 19:54:00]

LGTM, though I am not sure what the answer is to joth's comment about version
mismatch.  There will be no version mismatch for the SDK (i.e. non webview)
builds.  For webview builds I'm not sure what the include path is.