Revert "Revert "Display: Dirty region propagation""

This reverts commit 07a578dd7df84f949ec82c858aeb5f0f332cdbff.
Revert "Revert "FileUtils fixes""

This reverts commit 32f2ff02538c30759daa924aeb1a039740fc54a4.
Revert "Revert "Put FileUtils back into android_runtime""

This reverts commit 35c92aa64c7edc5c17a2ef4d7b43e652cc76dd23.