Run-test: Refactor stdout/stderr capture

Capture only the stdout/stderr of the dalvikvm command.

This allows us to echo debugging commands within `adb shell`.

This change will be necessary for the runners scripts as well.

Test: ./art/test.py -r --all-target --optimizing --64
Change-Id: Ic0cd0baac5238f220323fd0a930f58164591119f
1 file changed