Re-enable tests with the optimizing compiler.

Tests run ok on my host/target. I reverted the move to
using thumb2, because tests were crashing. But I could not
reproduce file limits issues.

Make SignalTest as crashing for optimizing. We need to implement
stack overflow checks.

Change-Id: Ieda575501eaf30af7aaa2c44e71544c9c467c24f
diff --git a/compiler/optimizing/code_generator_arm.h b/compiler/optimizing/code_generator_arm.h
index 0e2a079..712a24c 100644
--- a/compiler/optimizing/code_generator_arm.h
+++ b/compiler/optimizing/code_generator_arm.h
@@ -20,7 +20,7 @@
 #include "code_generator.h"
 #include "nodes.h"
 #include "parallel_move_resolver.h"
-#include "utils/arm/assembler_thumb2.h"
+#include "utils/arm/assembler_arm32.h"
 
 namespace art {
 namespace arm {
@@ -180,7 +180,7 @@
   LocationsBuilderARM location_builder_;
   InstructionCodeGeneratorARM instruction_visitor_;
   ParallelMoveResolverARM move_resolver_;
-  Thumb2Assembler assembler_;
+  Arm32Assembler assembler_;
 
   DISALLOW_COPY_AND_ASSIGN(CodeGeneratorARM);
 };