Promote pointer to dex cache arrays on arm.

Do the use-count analysis on temps (ArtMethod* and the new
PC-relative temp) in Mir2Lir, rather than MIRGraph. MIRGraph
isn't really supposed to know how the ArtMethod* is used by
the backend.

Change-Id: Iaf56a46ae203eca86281b02b54f39a80fe5cc2dd
diff --git a/compiler/dex/quick/arm/target_arm.cc b/compiler/dex/quick/arm/target_arm.cc
index 580dcb7..5f27338 100644
--- a/compiler/dex/quick/arm/target_arm.cc
+++ b/compiler/dex/quick/arm/target_arm.cc
@@ -576,7 +576,8 @@
 ArmMir2Lir::ArmMir2Lir(CompilationUnit* cu, MIRGraph* mir_graph, ArenaAllocator* arena)
     : Mir2Lir(cu, mir_graph, arena),
       call_method_insns_(arena->Adapter()),
-      dex_cache_access_insns_(arena->Adapter()) {
+      dex_cache_access_insns_(arena->Adapter()),
+      dex_cache_arrays_base_reg_(RegStorage::InvalidReg()) {
   call_method_insns_.reserve(100);
   // Sanity check - make sure encoding map lines up.
   for (int i = 0; i < kArmLast; i++) {