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/intern_table.h b/runtime/intern_table.h
index 24c5af9..3a4e8d8 100644
--- a/runtime/intern_table.h
+++ b/runtime/intern_table.h
@@ -146,6 +146,7 @@
   // weak interns and strong interns.
   class Table {
    public:
+    Table();
     mirror::String* Find(mirror::String* s) SHARED_REQUIRES(Locks::mutator_lock_)
         REQUIRES(Locks::intern_table_lock_);
     void Insert(mirror::String* s) SHARED_REQUIRES(Locks::mutator_lock_)