This CL modifies the ast-numbering phase to collect function literals which
should be compiled eagerly. This is then used to eagerly compile the inner
functions before compiling the outer function. This will be used to queue
compilation jobs on the CompilerDispatcher in a later CL.

This CL moves the compilation of eager inner functions out of the
GetSharedFunctionInfo function and instead compiles them explicitly. This
simplifies GetSharedFunctionInfo and also means there is no need to pass a
LazyCompilationMode to the function, so this concept has been removed.

BUG=v8:5203,v8:5215

Review-Url: https://codereview.chromium.org/2618553004
Cr-Commit-Position: refs/heads/master@{#42221}