Repair x64 disassembler:
Repair x64 disassembler:

- fix disassembler constructor to initialize fields correctly;
- move more code from InstructionDecode to DecodeInstructionType, this ensures that it'll use the right value of current variable (which is not always equal to **data as it assumed before).

R=kmillikin@google.com
BUG=

Review URL: https://chromiumcodereview.appspot.com//10825418

git-svn-id: c93d8a2297af3b929165606efe145742a534bc71@10898 260f80e4-7a28-3924-810f-c04153c831b5

dartino/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-lang/sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dartino/dart-sdk