Merge "Export mainDexClasses*.rules for MultiDexLegacy tests" am: 8ec286ef38 am: 8a1ce8888c am: 5f7ba6458f

Original change: https://android-review.googlesource.com/c/platform/dalvik/+/1828916

Change-Id: I2dd3c063594ecebc31d22441d7e204d154c4a6f6