Various things.

This patch:

1. adds good-enough implementations for a couple of Class native methods we
need.

2. removes a fixed TODO from image_test.

3. adds missing null checks to the Thread native methods, and forwards
Thread.nativeCreate to Thread::Create.

4. stops jni_compiler from overwriting already-registered native methods
with the dynamic lookup stub.

5. adds workarounds to Thread::CreatePeer so we can cope better without
code, attempts to initialize thread groups correctly, dumps thread state
from the managed peer (where one exists), and implements Thread::DumpStack
for debugging (and SIGQUIT dumps).

Change-Id: I3281226dd22ec852dca5165748fc75a254904ac0
diff --git a/build/Android.common.mk b/build/Android.common.mk
index 046fbbe..b4fb7aa 100644
--- a/build/Android.common.mk
+++ b/build/Android.common.mk
@@ -76,6 +76,7 @@
 	src/image_writer.cc \
 	src/indirect_reference_table.cc \
 	src/intern_table.cc \
+	src/java_lang_Class.cc \
 	src/java_lang_Object.cc \
 	src/java_lang_Runtime.cc \
 	src/java_lang_String.cc \