Merge "[optimizing] Add basic PackedSwitch support"

diff --cc compiler/optimizing/code_generator_arm.cc
Simple merge

diff --cc compiler/optimizing/code_generator_arm64.cc
Simple merge

diff --cc compiler/optimizing/code_generator_mips64.cc
Simple merge

diff --cc compiler/optimizing/code_generator_x86.cc
Simple merge

diff --cc compiler/optimizing/code_generator_x86_64.cc
Simple merge