rustdoc: fix the search-bar layout

Now with broader compatibility.
Remove -Z coherence
Fixed a minor typo.
Fix missing code map entry for uses of `include_str!`.
proto is gone

The following files need to be adjusted, too (i can't do it now):
- doc/po/ja/rust.md.po
- doc/po/rust.md.pot
Some rustdoc manual fixes

Clarify that it's sundown, and that we don't support magic
Disable all unwinding on -Z no-landing-pads LTO

When performing LTO, the rust compiler has an opportunity to completely strip
all landing pads in all dependent libraries. I've modified the LTO pass to
recognize the -Z no-landing-pads option when also running an LTO pass to flag
everything in LLVM as nothrow. I've verified that this prevents any and all
invoke instructions from being emitted.

I believe that this is one of our best options for moving forward with
accomodating use-cases where unwinding doesn't really make sense. This will
allow libraries to be built with landing pads by default but allow usage of them
in contexts where landing pads aren't necessary.

cc #10780
Upgrade libuv with an OSX build system fix

This allows building of libuv for android with a host OS of OSX.
Make priv members of extra::stats::Summary public.
Embed Windows application manifest.
Add std::io::util

This adds a bunch of useful Reader and Writer implementations. I'm not a
huge fan of the name `util` but I can't think of a better name and I
don't want to make `std::io` any longer than it already is.
Make base64::config fields public again

These got swept up in the great privatizing of 2013.
Don't always modify the symbol table in rlibs

Turns out that one some platforms the ar/ranlib tool will die with an assertion
if the file being added doesn't actually have any symbols (or if it's just not
an object file presumably).

This functionality is already all exercised on the bots, it just turns out that
the bots don't have an ar tool which dies in this situation, so it's difficult
for me to add a test.

Closes #10907
Inline Finallyalizer::drop, allowing LLVM to optimize `finally`.
* fixes the vec::from_elem regression caused by #8780
* added 5 benchmarks for allocating a 1KB ~[u8] and zeroing it
Fixed "unused variable" errors and trailing whitespace.
Gate literal box expressions in addition to types

Closes #10920
Remove fk_anon
rewrite of shootout-fasta.rs

improvements:
 - no managed box
 - no virtual calls
 - no useless copy
 - optimizations (bisect is slower, limit tests, BufferedWriter...)
 - pass shootout test
 - should be as fast as the best official test

Thanks to @cmr and @eddyb for their help!
Use libdir() instead of hard coded string. Fixes #10903
Add --dep-info to write Makefile-compatible dependency info.

When --dep-info is given, rustc will write out a `$input_base.d` file in the
output directory that contains Makefile compatible dependency information for
use with tools like make and ninja.