Add "add immediate" instruction to the ARM integrated assembler.

src/DartARM32/assembler_arm.cc

Index: src/DartARM32/assembler_arm.cc
diff --git a/src/DartARM32/assembler_arm.cc b/src/DartARM32/assembler_arm.cc
index ec942d053a4f4c46306578d2e60bfe46a92b1606..91c8d8873d98ceb73c8fac4907af3f1babc08f9c 100644
--- a/src/DartARM32/assembler_arm.cc
+++ b/src/DartARM32/assembler_arm.cc
@@ -208,6 +208,8 @@ void Assembler::rsbs(Register rd, Register rn, Operand o, Condition cond) {
 }
 
 
+#if 0
+// Moved to IceAssemberARM32::add.
 void Assembler::add(Register rd, Register rn, Operand o, Condition cond) {
   EmitType01(cond, o.type(), ADD, 0, rn, rd, o);
 }
@@ -216,6 +218,7 @@ void Assembler::add(Register rd, Register rn, Operand o, Condition cond) {
 void Assembler::adds(Register rd, Register rn, Operand o, Condition cond) {
   EmitType01(cond, o.type(), ADD, 1, rn, rd, o);
 }
+#endif
 
 
 void Assembler::subs(Register rd, Register rn, Operand o, Condition cond) {