Fixed RunCommandDropRoot when running as Shell.

BUG: 26379932
BUG: 31807540

Test: mmm -j32 frameworks/native/cmds/dumpstate/ && adb push ${ANDROID_PRODUCT_OUT}/data/nativetest/dumpstate_test* /data/nativetest&& adb unroot && adb shell /data/nativetest/dumpstate_test/dumpstate_test

Change-Id: Id582f5fbd4d6282a2eacce602ae1a6d1f62d5c61
2 files changed