This replaces a number of `#include`-s like this:
```
#include "../../../stdlib/public/SwiftShims/Visibility.h"
```
with this:
```
#include "swift/shims/Visibility.h"
```
This is needed to allow SwiftCompilerSources to use C++ headers which include SwiftShims headers. Currently trying to do that results in errors:
```
swift/swift/include/swift/Demangling/../../../stdlib/public/SwiftShims/module.modulemap:1:8: error: redefinition of module 'SwiftShims'
module SwiftShims {
^
Builds.noindex/swift/swift/bootstrapping0/lib/swift/shims/module.modulemap:1:8: note: previously defined here
module SwiftShims {
^
```
This happens because the headers in both the source dir and the build dir refer to SwiftShims headers by relative path, and both the source root and the build root contain SwiftShims headers (which are equivalent, but since they are located in different dirs, Clang treats them as different modules).
Crash reporter integration was only enabled for iOS. Enable it for
any Darwin platform, but disable it for the minimal build.
Also fix up a couple of issues that popped up when it was enabled.
rdar://89139049
The demangling library can't use the error handling from the main runtime
because it isn't always linked with it. However, it's useful to have
some error handling, and in particular to be able to get data into the
crash logs.
This is complicated because of the way the demangling library gets used,
the upshot of which is that I've had to add a second object library just
for libswiftCore's use, so that the demangler will use the runtime's
error handling functions when present, and fall back on its own when
they aren't.
rdar://89139049
