Quick: Kill unreachable blocks instead of just hiding them.

This changes the block type from kDalvikByteCode to kDead
and properly cleans up predecessors and MIRGraph::catches_.

Bug: 18626174
Change-Id: I268bf68f7947604bcb82caf95ee79c6831ee6e2a
diff --git a/compiler/dex/ssa_transformation.cc b/compiler/dex/ssa_transformation.cc
index ed33882..b803462 100644
--- a/compiler/dex/ssa_transformation.cc
+++ b/compiler/dex/ssa_transformation.cc
@@ -104,11 +104,11 @@
   num_reachable_blocks_ = dfs_order_.size();
 
   if (num_reachable_blocks_ != num_blocks_) {
-    // Hide all unreachable blocks.
+    // Kill all unreachable blocks.
     AllNodesIterator iter(this);
     for (BasicBlock* bb = iter.Next(); bb != NULL; bb = iter.Next()) {
       if (!bb->visited) {
-        bb->Hide(this);
+        bb->Kill(this);
       }
     }
   }