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

(cherry picked from commit 12f7423a2bb4bfab76700d84eb6d4338d211983a)

Bug: 18588862
Change-Id: Ic5a2781f704e931265ffb3621c2eab4b2e25f60f

1 files changed, 14 insertions, 0 deletions

diff --git a/runtime/stack.h b/runtime/stack.h
index 15007af..233e1c3 100644
--- a/runtime/stack.h
+++ b/runtime/stack.h
@@ -22,6 +22,7 @@
 
 #include "arch/instruction_set.h"
 #include "dex_file.h"
+#include "gc_root.h"
 #include "mirror/object_reference.h"
 #include "throw_location.h"
 #include "utils.h"
@@ -314,6 +315,19 @@ class ShadowFrame {
   DISALLOW_IMPLICIT_CONSTRUCTORS(ShadowFrame);
 };
 
+class JavaFrameRootInfo : public RootInfo {
+ public:
+  JavaFrameRootInfo(uint32_t thread_id, const StackVisitor* stack_visitor, size_t vreg)
+     : RootInfo(kRootJavaFrame, thread_id), stack_visitor_(stack_visitor), vreg_(vreg) {
+  }
+  virtual void Describe(std::ostream& os) const OVERRIDE
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+
+ private:
+  const StackVisitor* const stack_visitor_;
+  const size_t vreg_;
+};
+
 // The managed stack is used to record fragments of managed code stacks. Managed code stacks
 // may either be shadow frames or lists of frames using fixed frame sizes. Transition records are
 // necessary for transitions between code using different frame layouts and transitions into native