Modular build: Fix tests to not assume the cwd is "modular-build"
Modular build: Fix tests to not assume the cwd is "modular-build"

Find the "examples" dir relative to the Python module's location.

BUG=none
TEST=python tools/modular-build/test_all.py

Review URL: http://codereview.chromium.org/3192005

git-svn-id: 721b910a23eff8a86f00c8fd261a7587cddf18f8@3038 fcba33aa-ac0c-11dd-b9e7-8d5594d729c2

nacl-webkit/native_client,sbc100/native_client,sbc100/native_client,nacl-webkit/native_client,sbc100/native_client,sbc100/native_client,nacl-webkit/native_client,nacl-webkit/native_client,sbc100/native_client,sbc100/native_client,nacl-webkit/native_client