Dedupe inherited jsdoc comments

[sandersn]

JSDoc on own properties was already deduped, but inherited jsdoc was incorrectly not deduped.

Fixes #32708

[mihailik]

Is there a plan to converge duplicate JSDoc in lib.d.ts on the back of this change?

It would be great!

See lib.es5.d.ts starting at line 1162 for example:

    /**
     * Returns the elements of an array that meet the condition specified in a callback function.
     * @param callbackfn A function that accepts up to three arguments. The filter method calls the callbackfn function one time for each element in the array.
     * @param thisArg An object to which the this keyword can refer in the callbackfn function. If thisArg is omitted, undefined is used as the this value.
     */
    filter<S extends T>(callbackfn: (value: T, index: number, array: readonly T[]) => value is S, thisArg?: any): S[];
    /**
     * Returns the elements of an array that meet the condition specified in a callback function.
     * @param callbackfn A function that accepts up to three arguments. The filter method calls the callbackfn function one time for each element in the array.
     * @param thisArg An object to which the this keyword can refer in the callbackfn function. If thisArg is omitted, undefined is used as the this value.
     */
    filter(callbackfn: (value: T, index: number, array: readonly T[]) => unknown, thisArg?: any): T[];




    /**
     * Calls the specified callback function for all the elements in an array. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
     * @param callbackfn A function that accepts up to four arguments. The reduce method calls the callbackfn function one time for each element in the array.
     * @param initialValue If initialValue is specified, it is used as the initial value to start the accumulation. The first call to the callbackfn function provides this value as an argument instead of an array value.
     */
    reduce(callbackfn: (previousValue: T, currentValue: T, currentIndex: number, array: readonly T[]) => T): T;
    reduce(callbackfn: (previousValue: T, currentValue: T, currentIndex: number, array: readonly T[]) => T, initialValue: T): T;
    /**
     * Calls the specified callback function for all the elements in an array. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
     * @param callbackfn A function that accepts up to four arguments. The reduce method calls the callbackfn function one time for each element in the array.
     * @param initialValue If initialValue is specified, it is used as the initial value to start the accumulation. The first call to the callbackfn function provides this value as an argument instead of an array value.
     */
    reduce<U>(callbackfn: (previousValue: U, currentValue: T, currentIndex: number, array: readonly T[]) => U, initialValue: U): U;

[sandersn]

This change is unrelated, it just prevents dupes in the quick info display. This arises from multiple declarations on the same symbol, but that's already prevented for overloads.