Clean up code to clarify we are only tracking the condition flags of APSR.

src/trusted/validator_arm/validator.h

Index: src/trusted/validator_arm/validator.h
===================================================================
--- src/trusted/validator_arm/validator.h	(revision 8564)
+++ src/trusted/validator_arm/validator.h	(working copy)
@@ -228,7 +228,7 @@
    */
   bool always_follows(const DecodedInstruction &other) const {
     return inst_.condition() == other.inst_.condition()
-        && !other.defines(nacl_arm_dec::kRegisterFlags);
+        && !other.defines(nacl_arm_dec::kConditions);
   }
 
   /*
@@ -239,7 +239,7 @@
   bool is_conditional_on(const DecodedInstruction &other) const {
     return inst_.condition() == nacl_arm_dec::Instruction::EQ
         && other.inst_.condition() == nacl_arm_dec::Instruction::AL
-        && other.defines(nacl_arm_dec::kRegisterFlags);
+        && other.defines(nacl_arm_dec::kConditions);
   }
 
   // The methods below mirror those on ClassDecoder, but are cached and cheap.