fix(language-service): Improve signature selection by finding exact match (#37494)

The function signature selection algorithm is totally naive. It'd
unconditionally pick the first signature if there are multiple
overloads. This commit improves the algorithm by returning an exact
match if one exists.

PR Close #37494

packages/language-service/test/project/app/main.ts

@@ -22,6 +22,7 @@ import * as ParsingCases from './parsing-cases';
     ParsingCases.StringModel,
     ParsingCases.TemplateReference,
     ParsingCases.TestComponent,
+    ParsingCases.TestPipe,
     ParsingCases.WithContextDirective,
   ]
 })

packages/language-service/test/project/app/parsing-cases.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {Component, Directive, EventEmitter, Input, OnChanges, Output, SimpleChanges, TemplateRef, ViewContainerRef} from '@angular/core';
+import {Component, Directive, EventEmitter, Input, OnChanges, Output, Pipe, PipeTransform, SimpleChanges, TemplateRef, ViewContainerRef} from '@angular/core';
 
 import {Hero} from './app.component';
 
@@ -69,6 +69,20 @@ export class WithContextDirective {
   }
 }
 
+@Pipe({
+  name: 'prefixPipe',
+})
+export class TestPipe implements PipeTransform {
+  transform(value: string, prefix: string): string;
+  transform(value: number, prefix: number): number;
+  transform(value: string|number, prefix: string|number): string|number {
+    if (typeof value === 'string') {
+      return `${prefix} ${value}`;
+    }
+    return parseInt(`${prefix}${value}`, 10 /* radix */);
+  }
+}
+
 /**
  * This Component provides the `test-comp` selector.
  */