8048869: Reduce compile time by about 5% by removing the Class.casts from the AST nodes
Summary: Removed the native casts that slow down the compiler unnecessarily. I also modified the compile-octane harness so that it can run with --verbose and --iterations flags so that you can run the compiler for an arbitrary time, gathering a mission control executing profile.
Reviewed-by: attila, jlaskey
Compiling 'box2d'...
Done.
Compiling 'code-load'...
Done.
Compiling 'crypto'...
Done.
Compiling 'deltablue'...
Done.
Compiling 'earley-boyer'...
Done.
Compiling 'gbemu'... (2 files)
Done.
Compiling 'mandreel'...
Done.
Compiling 'navier-stokes'...
Done.
Compiling 'pdfjs'...
Done.
Compiling 'raytrace'...
Done.
Compiling 'regexp'...
Done.
Compiling 'richards'...
Done.
Compiling 'splay'...
Done.
Compiling 'typescript'... (3 files)
Done.
Compiling 'zlib'... (2 files)
Done.