Optimizing: Tag arena allocations in HGraph.

Replace GrowableArray with ArenaVector in HGraph and related
classes HEnvironment, HLoopInformation, HInvoke and HPhi,
and tag allocations with new arena allocation types.

Change-Id: I3d79897af405b9a1a5b98bfc372e70fe0b3bc40d
diff --git a/compiler/optimizing/optimizing_unit_test.h b/compiler/optimizing/optimizing_unit_test.h
index 86c22ed..350f0b1 100644
--- a/compiler/optimizing/optimizing_unit_test.h
+++ b/compiler/optimizing/optimizing_unit_test.h
@@ -60,10 +60,8 @@
 }
 
 void RemoveSuspendChecks(HGraph* graph) {
-  for (size_t i = 0, e = graph->GetBlocks().Size(); i < e; ++i) {
-    for (HInstructionIterator it(graph->GetBlocks().Get(i)->GetInstructions());
-         !it.Done();
-         it.Advance()) {
+  for (HBasicBlock* block : graph->GetBlocks()) {
+    for (HInstructionIterator it(block->GetInstructions()); !it.Done(); it.Advance()) {
       HInstruction* current = it.Current();
       if (current->IsSuspendCheck()) {
         current->GetBlock()->RemoveInstruction(current);