Fix ARM build for changes to VirtualFrame

src/virtual-frame-arm.cc

Index: src/virtual-frame-arm.cc
===================================================================
--- src/virtual-frame-arm.cc	(revision 1595)
+++ src/virtual-frame-arm.cc	(working copy)
@@ -52,6 +52,9 @@
   for (int i = 0; i < parameter_count_ + 1; i++) {
     elements_.Add(FrameElement::MemoryElement());
   }
+  for (int i = 0; i < kNumRegisters; i++) {
+    register_locations_[i] = kIllegalIndex;
+  }
 }