Revert "Optimizing: Tag basic block allocations with their source."

Reverting so that we can have more discussion about the STL API.

This reverts commit 91e11c0c840193c6822e66846020b6647de243d5.

Change-Id: I187fe52f2c16b6e7c5c9d49c42921eb6c7063dba
diff --git a/runtime/base/arena_allocator.cc b/runtime/base/arena_allocator.cc
index a36b0fb..3a4bccd 100644
--- a/runtime/base/arena_allocator.cc
+++ b/runtime/base/arena_allocator.cc
@@ -52,14 +52,13 @@
   "SSA2Dalvik   ",
   "Dalvik2SSA   ",
   "DebugInfo    ",
+  "Successor    ",
   "RegAlloc     ",
   "Data         ",
+  "Preds        ",
   "STL          ",
   "Graph        ",
   "BasicBlock   ",
-  "Predecessors ",
-  "Successors   ",
-  "Dominated    ",
   "Instruction  ",
   "LoopInfo     ",
   "TryCatchInf  ",