Fast path interface dispatch.

Interface dispatch when the method we're dispatching against is known
currently goes slow path. This change makes the load of the interface
method either a load of a constant or from the resolve methods table. It
also makes the null check on the "this" pointer inline.

Change-Id: I69571a062d3d693bee2dec6e46a456e0f74411cd
diff --git a/src/disassembler_arm.cc b/src/disassembler_arm.cc
index 509755c..dfaacf2 100644
--- a/src/disassembler_arm.cc
+++ b/src/disassembler_arm.cc
@@ -1006,7 +1006,7 @@
         ThumbRegister Rt(instr, 8);
         uint16_t imm8 = instr & 0xFF;
         opcode << (opB == 0 ? "str" : "ldr");
-        args << Rt << ", [ sp, #" << (imm8 << 2) << "]";
+        args << Rt << ", [sp, #" << (imm8 << 2) << "]";
       } else {
         uint16_t imm5 = (instr >> 6) & 0x1F;
         uint16_t opB = (instr >> 11) & 1;