[assembler] Introduce proper AssemblerBase::Print() for improved debuggability.

test/cctest/test-disasm-arm64.cc

Index: test/cctest/test-disasm-arm64.cc
diff --git a/test/cctest/test-disasm-arm64.cc b/test/cctest/test-disasm-arm64.cc
index 643a3c1bdbd122a6003e3d2c37173b1d5be31b5c..357bfc5ad96a454b3101674cc8a88e4ec91f62dd 100644
--- a/test/cctest/test-disasm-arm64.cc
+++ b/test/cctest/test-disasm-arm64.cc
@@ -45,16 +45,16 @@ using namespace v8::internal;
 
 #define EXP_SIZE   (256)
 #define INSTR_SIZE (1024)
-#define SET_UP_CLASS(ASMCLASS)                             \
-  InitializeVM();                                          \
-  Isolate* isolate = Isolate::Current();                   \
-  HandleScope scope(isolate);                              \
-  byte* buf = static_cast<byte*>(malloc(INSTR_SIZE));      \
-  uint32_t encoding = 0;                                   \
-  ASMCLASS* assm = new ASMCLASS(isolate, buf, INSTR_SIZE); \
-  Decoder<DispatchingDecoderVisitor>* decoder =            \
-      new Decoder<DispatchingDecoderVisitor>();            \
-  Disassembler* disasm = new Disassembler();               \
+#define SET_UP_CLASS(ASMCLASS)                               \
+  InitializeVM();                                            \
+  Isolate* isolate = Isolate::Current();                     \
+  HandleScope scope(isolate);                                \
+  byte* buf = static_cast<byte*>(malloc(INSTR_SIZE));        \
+  uint32_t encoding = 0;                                     \
+  ASMCLASS* assm = new ASMCLASS(isolate, buf, INSTR_SIZE);   \
+  Decoder<DispatchingDecoderVisitor>* decoder =              \
+      new Decoder<DispatchingDecoderVisitor>();              \
+  DisassemblingDecoder* disasm = new DisassemblingDecoder(); \
   decoder->AppendVisitor(disasm)
 
 #define SET_UP() SET_UP_CLASS(Assembler)