Refactor findAllReferences. Now supports renamed exports and imports.

[ghost]

Don't think there was an issue for this but was mentioned here: #13643 (comment).
Fixes #13663.
Update: Now also fixes #10894.
Update: Fixes #14103.
We now use an algorithm to search for imports of a given export. This is in the new importTracker.ts. Previously we would just globally search for identifiers with the same name.

Note: This breaks find-all-refs for untyped modules since we want to match the symbol and not just the name. See #14002.

[mhegazy]

Some comments:

• getReferencesForStringLiteral, why does it use type

• getReferencesInContainer, consider passing in the containig sourceFile

• searchForImportsOfExport, consider changing the switch in the IIFE to just set a variable

• sourceFileHasName, consider inlining this at use site

• getSymbolScope, consider making the comment more detailed for export as namespace

• getDirectImportsMap, I would change the map to use a Map object instead

• export assignment handling, export = foo, export default foo

• consider renaming isProperImportEquals to isExternalModuleImportEqual

• forEachImport, consider storing the require calls on the sourceFile like we do with the imports
  this makes forEachPossibleImportOrExportStatement jsut a walk over ambient modules

• getImportOrExportSymbol, consider changing the return expression to return comingFromExport ? getExport() : getExport() || getImport();

• getExport, make sure to check comingFromExport before return an import

• isNodeImport, in case for ImportEqualsDeclaration, check for is it an import .. = require or just an import .. = X

• nodeIsEligibleForRename, check the parent of the node to make sure it is an import or export specifier, and worth adding a test of x.default vs a case of import * as ns from "mod"; ns.default;

[mhegazy]

@Andy-MS can you also validate that this change addresses #14346 and

[ghost]

@mhegazy Should all be done except for #14880, which I assigned to myself.

[mhegazy]

@Andy-MS i still do not see #14346 with this change..

[ghost]

Should be in 28a3604