Provide better coverage of jitted methods to the profiler.

Provide better coverage of jitted methods to the profiler.

Sometimes we use wrapper methods or other tricks under the hood,
but we provided to the profiler some inconsistent information,
for example the MonoMethod pointer in enter/leave events could be
different from the one used in reporting jit compilation.
This patch introduces a concept of aliased methods: more
than one MonoMethod pointer could correspond to the same jit info
and as such, more end_jit notifications can happen for the same
compiled code. This also means, in turn, that you can get a
end_jit notification for MonoMethod pointers that weren't reported
in a start_jit event.
This partially reverts the change in 2e0067422b9cb, which doesn't
have an associated bug report anyway (this change instead fixes
the issue with unresolved methods in the log profiler).