Ignore -Wunreachable-code for ClassTable::UpdateClass

Bug: http://b/30421084
Bug: http://b/31104323

Clang triggers -Wunreachable-code in runtime/class_table.cc.  Disable
the one instance of this warning until we can investigate (and fix) the
Clang regression.

Change-Id: Ib292009c6d639f540d6b31e793d8aa89dd861b9e
Test: Tested build, boot and common usage for several devices images in
AOSP and internal branch.
1 file changed