[Android] Fix that make_apk_test fails when out/ has both ARM and x86 builds

Both testCustomizeFile and testEmptyMode fail when out happens to have
both an ARM and an x86 build: in this case, the ARM native libraries will be around
and make_apk.py will generate both ARM and x86 APKs,
making the self.assertFalse(os.path.isfile('Example_1.0.0_arm.apk')) call fail.

BUG=https://crosswalk-project.org/jira/browse/XWALK-1466
[Android] Try to match cpu arch after loading xwalk core

It's extremely slow to load ARM binaries on ia devices.
And it hurts user experience. Add a method in libxwalkcore.so
to tell XWalkViewDelegate whether the binary is built for IA.

The exception of CPU architecture mismatch will be handled
by XWalkView instead of dispatch to runtime level or embedders.

A AlertDialog will be shown to notify user what's wrong and
suggest them report feedback to application developers or
rate and comment the application on PlayStore.

BUG=https://crosswalk-project.org/jira/browse/XWALK-1283
Merge pull request #1764 from wang16/warn_arm_on_ia

[Android] Try to match cpu arch before loading xwalk core
Merge pull request #1835 from jinbang/fix_make_apk_test_fail

[Android] Fix that make_apk_test fails when out/ has both ARM and x86 bu...