Print more info in MarkSweep::VerifyRoot

Refactored old root callback to use a new class called RootInfo.
RootInfo contains all the relevant info related to the root
associated with the callback. The MarkSweep::VerifyRoot function
now uses this info to print the StackVisitor's described location
if the GC root is of the type kRootJavaFrame.

Some other cleanup.

Example output:
E/art     (12167): Tried to mark 0x123 not contained by any spaces
E/art     (12167): Attempting see if it's a bad root
E/art     (12167): Found invalid root: 0x123 with type RootJavaFrame
E/art     (12167): Location=Visiting method
'void java.lang.Runtime.gc()' at dex PC 0xffffffff (native PC 0x0)
vreg=0

Bug: 18588862
Change-Id: Ic5a2781f704e931265ffb3621c2eab4b2e25f60f
diff --git a/runtime/Android.mk b/runtime/Android.mk
index 0f5050b..84f2248 100644
--- a/runtime/Android.mk
+++ b/runtime/Android.mk
@@ -298,6 +298,7 @@
   base/unix_file/fd_file.h \
   dex_file.h \
   dex_instruction.h \
+  gc_root.h \
   gc/collector/gc_type.h \
   gc/collector_type.h \
   gc/space/space.h \
@@ -310,7 +311,6 @@
   lock_word.h \
   mirror/class.h \
   oat.h \
-  object_callbacks.h \
   quick/inline_method_analyser.h \
   thread.h \
   thread_state.h \