Extract hardcoded error strings into a single place and replace them with enum.

src/arm/codegen-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 514 matching lines @@
   __ add(r7, r7, Operand(8));
   __ b(&entry);
 
   // Hole found, store the-hole NaN.
   __ bind(&convert_hole);
   if (FLAG_debug_code) {
     // Restore a "smi-untagged" heap object.
     __ SmiTag(r9);
     __ orr(r9, r9, Operand(1));
     __ CompareRoot(r9, Heap::kTheHoleValueRootIndex);
-    __ Assert(eq, "object found in smi-only array");
+    __ Assert(eq, kObjectFoundInSmiOnlyArray);
   }
   __ Strd(r4, r5, MemOperand(r7, 8, PostIndex));
 
   __ bind(&entry);
   __ cmp(r7, r6);
   __ b(lt, &loop);
 
   __ pop(lr);
   __ bind(&done);
 }
@@ skipping 175 matching lines @@
          string,
          Operand(SeqTwoByteString::kHeaderSize - kHeapObjectTag));
   __ jmp(&check_encoding);
 
   // Handle external strings.
   __ bind(&external_string);
   if (FLAG_debug_code) {
     // Assert that we do not have a cons or slice (indirect strings) here.
     // Sequential strings have already been ruled out.
     __ tst(result, Operand(kIsIndirectStringMask));
-    __ Assert(eq, "external string expected, but not found");
+    __ Assert(eq, kExternalStringExpectedButNotFound);
   }
   // Rule out short external strings.
   STATIC_CHECK(kShortExternalStringTag != 0);
   __ tst(result, Operand(kShortExternalStringMask));
   __ b(ne, call_runtime);
   __ ldr(string, FieldMemOperand(string, ExternalString::kResourceDataOffset));
 
   Label ascii, done;
   __ bind(&check_encoding);
   STATIC_ASSERT(kTwoByteStringTag == 0);
@@ skipping 142 matching lines @@
     patcher.masm()->add(r0, pc, Operand(-8));
     patcher.masm()->ldr(pc, MemOperand(pc, -4));
     patcher.masm()->dd(reinterpret_cast<uint32_t>(stub->instruction_start()));
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM