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, 2 insertions, 4 deletions

diff --git a/runtime/java_vm_ext.cc b/runtime/java_vm_ext.cc
index 7f677ab5d3..4643d145cc 100644
--- a/runtime/java_vm_ext.cc
+++ b/runtime/java_vm_ext.cc
@@ -764,10 +764,8 @@ void JavaVMExt::TrimGlobals() {
 
 void JavaVMExt::VisitRoots(RootCallback* callback, void* arg) {
   Thread* self = Thread::Current();
-  {
-    ReaderMutexLock mu(self, globals_lock_);
-    globals_.VisitRoots(callback, arg, 0, kRootJNIGlobal);
-  }
+  ReaderMutexLock mu(self, globals_lock_);
+  globals_.VisitRoots(callback, arg, RootInfo(kRootJNIGlobal));
   // The weak_globals table is visited by the GC itself (because it mutates the table).
 }