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
diff --git a/runtime/gc/heap.cc b/runtime/gc/heap.cc
index 618f1cc..553a5d3 100644
--- a/runtime/gc/heap.cc
+++ b/runtime/gc/heap.cc
@@ -2236,8 +2236,8 @@
   gc_complete_cond_->Broadcast(self);
 }
 
-static void RootMatchesObjectVisitor(mirror::Object** root, void* arg, uint32_t /*thread_id*/,
-                                     RootType /*root_type*/) {
+static void RootMatchesObjectVisitor(mirror::Object** root, void* arg,
+                                     const RootInfo& /*root_info*/) {
   mirror::Object* obj = reinterpret_cast<mirror::Object*>(arg);
   if (*root == obj) {
     LOG(INFO) << "Object " << obj << " is a root";
@@ -2279,12 +2279,12 @@
     return heap_->IsLiveObjectLocked(obj, true, false, true);
   }
 
-  static void VerifyRootCallback(mirror::Object** root, void* arg, uint32_t thread_id,
-                                 RootType root_type) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
+  static void VerifyRootCallback(mirror::Object** root, void* arg, const RootInfo& root_info)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     VerifyReferenceVisitor* visitor = reinterpret_cast<VerifyReferenceVisitor*>(arg);
     if (!visitor->VerifyReference(nullptr, *root, MemberOffset(0))) {
       LOG(ERROR) << "Root " << *root << " is dead with type " << PrettyTypeOf(*root)
-          << " thread_id= " << thread_id << " root_type= " << root_type;
+          << " thread_id= " << root_info.GetThreadId() << " root_type= " << root_info.GetType();
     }
   }