"run-ravenwood-tests.sh -r" for running tests in fbr.

- Also fixed the bug where the script stops when diff detests a change.
  (caused by addition of "-e"?)

Bug: 292141694
Flag: TEST_ONLY
Test: $ANDROID_BUILD_TOP/frameworks/base/ravenwood/scripts/run-ravenwood-tests.sh -s
Test: $ANDROID_BUILD_TOP/frameworks/base/ravenwood/scripts/run-ravenwood-tests.sh -r
Change-Id: If4be750c1f2cdabe81a7b98240263a18ccc59b87