Change BKPT and UDF encodings on ARM.

src/trusted/service_runtime/arch/arm/nacl_text_pad_test.S

Index: src/trusted/service_runtime/arch/arm/nacl_text_pad_test.S
diff --git a/src/trusted/service_runtime/arch/arm/nacl_text_pad_test.S b/src/trusted/service_runtime/arch/arm/nacl_text_pad_test.S
index 27ba76630138c6b20cf6d6394f3217bcfd1010bf..fd5c296b42c4df0acdfe365d6616a9a1359083f0 100644
--- a/src/trusted/service_runtime/arch/arm/nacl_text_pad_test.S
+++ b/src/trusted/service_runtime/arch/arm/nacl_text_pad_test.S
@@ -3,10 +3,10 @@
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
+#include "native_client/src/include/arm_sandbox.h"
 #include "native_client/src/trusted/service_runtime/include/bits/nacl_syscalls.h"
 #include "native_client/src/trusted/service_runtime/nacl_config.h"
 
-#define halt 0xe1266676
 /* the macros below are used with movw/movt and absolute values */
 /* llvm-mc does not like the use of :lower16:/:upper16: with absolute values */
 /* c.f.: http://llvm.org/bugs/show_bug.cgi?id=8721 */
@@ -224,10 +224,11 @@ _start:
 /* NOTE: unlike x86 the alignment directive on ARM takes
    the logarithm of the alignment */
 #define POW2_BIGGER_THAN_DOT 14
-        .align32 POW2_BIGGER_THAN_DOT, halt
-        .fill (TEXT_EXTEND - (1 << POW2_BIGGER_THAN_DOT))/4, 4, halt
+        .align32 POW2_BIGGER_THAN_DOT, NACL_INSTR_HALT_FILL
+        .fill (TEXT_EXTEND - (1 << POW2_BIGGER_THAN_DOT))/4, 4, \
+              NACL_INSTR_HALT_FILL
 #else
-        .fill (TEXT_EXTEND - (. - start_of_text))/4, 4, halt
+        .fill (TEXT_EXTEND - (. - start_of_text))/4, 4, NACL_INSTR_HALT_FILL
 #endif
 
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