Inline function & Inline local

[D0nGiovanni]

Fixes #27070 and #18459.
Right now, inlining only works within a file, because I need to do all the checking beforehand in the getAvailableActions function. I fear that if I were to search the whole project, I would violate the performance requirement of getAvailableActions in case of large projects.

Both Inline function and Inline local work the same:

• Inline all: Replaces all usages in the file and deletes the declaration
• Inline here: Replaces the selected usage, but does not delete the declaration

Depending on some conditions in the canInline function, the refactoring may not be available. The user does not get feedback on why, though. I opened a related issue #28410, which adds reporting for refactorings to the tsserver interface, but it has not been implemented, yet.

[D0nGiovanni]

@RyanCavanaugh I hope this is what you meant by squashing. :)

[Kingwl]

It seems that there are many unrelated changes(a failed rebase?)... hope that you have the original changes

[D0nGiovanni]

Oh, thanks for noticing. I think I have an idea what went wrong.