1. Split FastNewArray from FastNewObject built-in for greater speed/specialization and further splitting into Array_1str, etc.
2. Add Array_1str, Array_2obj, and Array_3num builtins for benchmarked new Array(...) constructions.
3. Export ARRAY_SET_DENSE_LENGTH and ARRAY_GROWBY via jsarray.h to jstracer.cpp.
4. Tweaked SetArrayElement to make common/best case code be the predicted/prefetched path.
5. js_MakeArraySlow now preserves the pre-slow length in JSSLOT_ARRAY_COUTN as a jsval-tagged int if possible -- this will help the tracer avoid aborting on dense arrays that turned slow but not sparse by addition of a named property.
6. Export js_fun_apply and js_Object from their respective .cpp files, in these cases just to jstracer.cpp via local prototypes (no .h files involved).
7. More INS_CONSTPTR and INS_CONST macrology for better names in trace debug spew.
8. Fix TraceRecorder::test_property_cache to avoid aborting on JSOP_SETNAME that creates a new global, by setting it to undefined so it can be lazily imported. This helps 3d-raytrace.js, which has an unintended global loop control variable in a function.
9. JSTraceableNative loses its premature-deadwood tclasp member (my bad).
10. TraceRecorder::record_JSOP_NEW() handles 'new Object' now along with the 'new Array' variations. I also cut down the copy-paste code from JSOP_CALL's record method to mostly what is needed now.
11. Add KNOWN_NATIVE_DECL macro for concise prototype of library-private js_* native functions, and alphabetized the lists (too long for any other order to be winning).
12. Big honking special case for foo.apply(obj, [str]), which we can generalize as needed. Helps string-tagcloud.js. What's cool is how tracing allows us to rewrite this to foo(str) with this set to obj, eliminating the Function.prototype.apply. This requires some rewriting in JSOP_ENDINIT's record method.
