Quick: Improve the BBCombine pass.

Eliminate exception edges for insns that cannot throw even
when inside a try-block. Run the BBCombine pass before the
SSA transformation to reduce the compilation time.

Bug: 16398693
Change-Id: I8e91df593e316c994679b9d482b0ae20700b9499
diff --git a/compiler/dex/ssa_transformation.cc b/compiler/dex/ssa_transformation.cc
index dd74976..412f85d 100644
--- a/compiler/dex/ssa_transformation.cc
+++ b/compiler/dex/ssa_transformation.cc
@@ -108,10 +108,11 @@
     AllNodesIterator iter(this);
     for (BasicBlock* bb = iter.Next(); bb != NULL; bb = iter.Next()) {
       if (!bb->visited) {
-        bb->Hide(cu_);
+        bb->Hide(this);
       }
     }
   }
+  dfs_orders_up_to_date_ = true;
 }
 
 /*