Port 0a0fe8fb

Original commit message:

Import fdlibm versions of acos, acosh, asin and asinh, which are more
    precise and produce the same result across platforms (we were using
    libm versions for asin and acos so far, where both speed and precision
    depended on the operating system so far). Introduce appropriate TurboFan
    operators for these functions and use them both for inlining and for the
    generic builtin.

    Also migrate the Math.imul and Math.fround builtins to TurboFan builtins
    to ensure that their behavior is always exactly the same as the inlined
    TurboFan version (i.e. C++ truncation semantics for double to float
    don't necessarily meet the JavaScript semantics).

    For completeness, also migrate Math.sign, which can even get some nice
    love in TurboFan.

    Drive-by-fix: Some alpha-sorting on the Math related functions, and
    cleanup the list of Math intrinsics that we have to export via the
    native context currently.

R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com

BUG=v8:3266,v8:3496,v8:3509,v8:3952,v8:5169,v8:5170,v8:5171,v8:5172
LOG=N

Review-Url: https://codereview.chromium.org/2125723002
Cr-Commit-Position: refs/heads/master@{#37539}