Change hash table load factors

Changed class table and intern table load factors to query the
runtime. The runtime returns load factors based on whether or not we
are a low ram device.

DescriptorEquals time for class linking goes from 10% -> 1.2% for
compiling GmsCore with interpret only.

Added test.

Bug: 24917584

Change-Id: Iaaf5d2eab1b0c2d188d299e4bc1852cdb3801173
diff --git a/runtime/class_linker.h b/runtime/class_linker.h
index a70967d4..fd30a46 100644
--- a/runtime/class_linker.h
+++ b/runtime/class_linker.h
@@ -529,6 +529,8 @@
       SHARED_REQUIRES(Locks::mutator_lock_)
       REQUIRES(!Locks::classlinker_classes_lock_);
 
+  // Unlike GetOrCreateAllocatorForClassLoader, GetAllocatorForClassLoader asserts that the
+  // allocator for this class loader is already created.
   static LinearAlloc* GetAllocatorForClassLoader(mirror::ClassLoader* class_loader)
       SHARED_REQUIRES(Locks::mutator_lock_);