[Android] Correct the usage of all_dependent_settings for core library

Previously, the all_dependent_settings is incorrectly used
in xwalk_core_library.gypi.
It's not used to include all the settings for some target's
dependencies. It's actually do settings for all the targets
depends on the one declares all_dependent_settings.

BUG=https://crosswalk-project.org/jira/browse/XWALK-1575
Merge pull request #1926 from wang16/fix_core_library

[Android] Correct the usage of all_dependent_settings for core library