Avoid std::string allocations for finding an array class.

Introduce ClassLinker::FindArrayClass which performs an array class lookup
given the element/component class. This has a 16 element cache of recently
looked up arrays.
Pass the current thread to ClassLinker Find .. Class routines to avoid calls
to Thread::Current().
Avoid some uses of FindClass in the debugger where WellKnownClasses is a
faster and more compacting GC friendly alternative.

Change-Id: I60e231820b349543a7edb3ceb9cf1ce92db3c843

1 files changed, 2 insertions, 1 deletions

diff --git a/runtime/gc/heap_test.cc b/runtime/gc/heap_test.cc
index b02b8bb022..4b863397c4 100644
--- a/runtime/gc/heap_test.cc
+++ b/runtime/gc/heap_test.cc
@@ -43,7 +43,8 @@ TEST_F(HeapTest, GarbageCollectClassLinkerInit) {
     ScopedObjectAccess soa(Thread::Current());
     // garbage is created during ClassLinker::Init
 
-    SirtRef<mirror::Class> c(soa.Self(), class_linker_->FindSystemClass("[Ljava/lang/Object;"));
+    SirtRef<mirror::Class> c(soa.Self(), class_linker_->FindSystemClass(soa.Self(),
+                                                                        "[Ljava/lang/Object;"));
     for (size_t i = 0; i < 1024; ++i) {
       SirtRef<mirror::ObjectArray<mirror::Object> > array(soa.Self(),
           mirror::ObjectArray<mirror::Object>::Alloc(soa.Self(), c.get(), 2048));