Fix ndk-build warning in windows

When running ndk-build from jni/ directory, directory path is
expanded to full-path.  In windows, the full-path is completed
with drive letter and ':', eg. c:/path/to/project/jni.  As a
result, the following statement in "generate-dir" which is supposed
to ensure single rule for each directory since NDK r8c doesn't work
when $1 contain ':'.

  __ndk_dir_flag__$1 := true

The warning reads:
  ...android-ndk/build/core/build-binary.mk:350: warning: overriding commands for target c:/path/to/project/obj/local/armeabi
  ...android-ndk/build/core/build-binary.mk:350: warning: ignoring old commands for target c:/path/to/project/obj/local/armeabi

The solution is to use indirection via variable __ndk_dir instead.

See https://code.google.com/p/android/issues/detail?id=40192

Change-Id: Ic3f7016987e03440728d3d1b3282acb5afcdae9a
1 file changed