docs: fix pipe params (angular#42593)

The addition of overloads to some of the number pipes caused
the documentation to lose the parameter descriptions.

This change fixes that by moving the JSDOC block in from of the
primary method signature, rather than the first overload.

Fixes angular#42590

PR Close angular#42593

packages/common/src/pipes/number_pipe.ts

@@ -79,10 +79,10 @@ import {invalidPipeArgumentError} from './invalid_pipe_argument_error';
 @Pipe({name: 'number'})
 export class DecimalPipe implements PipeTransform {
   constructor(@Inject(LOCALE_ID) private _locale: string) {}
+
   transform(value: number|string, digitsInfo?: string, locale?: string): string|null;
   transform(value: null|undefined, digitsInfo?: string, locale?: string): null;
   transform(value: number|string|null|undefined, digitsInfo?: string, locale?: string): string|null;
-
   /**
    * @param value The value to be formatted.
    * @param digitsInfo Sets digit and decimal representation.
@@ -129,6 +129,9 @@ export class DecimalPipe implements PipeTransform {
 export class PercentPipe implements PipeTransform {
   constructor(@Inject(LOCALE_ID) private _locale: string) {}
 
+  transform(value: number|string, digitsInfo?: string, locale?: string): string|null;
+  transform(value: null|undefined, digitsInfo?: string, locale?: string): null;
+  transform(value: number|string|null|undefined, digitsInfo?: string, locale?: string): string|null;
   /**
    *
    * @param value The number to be formatted as a percentage.
@@ -145,9 +148,6 @@ export class PercentPipe implements PipeTransform {
    * When not supplied, uses the value of `LOCALE_ID`, which is `en-US` by default.
    * See [Setting your app locale](guide/i18n#setting-up-the-locale-of-your-app).
    */
-  transform(value: number|string, digitsInfo?: string, locale?: string): string|null;
-  transform(value: null|undefined, digitsInfo?: string, locale?: string): null;
-  transform(value: number|string|null|undefined, digitsInfo?: string, locale?: string): string|null;
   transform(value: number|string|null|undefined, digitsInfo?: string, locale?: string): string
       |null {
     if (!isValue(value)) return null;
@@ -207,6 +207,18 @@ export class CurrencyPipe implements PipeTransform {
       @Inject(LOCALE_ID) private _locale: string,
       @Inject(DEFAULT_CURRENCY_CODE) private _defaultCurrencyCode: string = 'USD') {}
 
+  transform(
+      value: number|string, currencyCode?: string,
+      display?: 'code'|'symbol'|'symbol-narrow'|string|boolean, digitsInfo?: string,
+      locale?: string): string|null;
+  transform(
+      value: null|undefined, currencyCode?: string,
+      display?: 'code'|'symbol'|'symbol-narrow'|string|boolean, digitsInfo?: string,
+      locale?: string): null;
+  transform(
+      value: number|string|null|undefined, currencyCode?: string,
+      display?: 'code'|'symbol'|'symbol-narrow'|string|boolean, digitsInfo?: string,
+      locale?: string): string|null;
   /**
    *
    * @param value The number to be formatted as currency.
@@ -240,18 +252,6 @@ export class CurrencyPipe implements PipeTransform {
    * When not supplied, uses the value of `LOCALE_ID`, which is `en-US` by default.
    * See [Setting your app locale](guide/i18n#setting-up-the-locale-of-your-app).
    */
-  transform(
-      value: number|string, currencyCode?: string,
-      display?: 'code'|'symbol'|'symbol-narrow'|string|boolean, digitsInfo?: string,
-      locale?: string): string|null;
-  transform(
-      value: null|undefined, currencyCode?: string,
-      display?: 'code'|'symbol'|'symbol-narrow'|string|boolean, digitsInfo?: string,
-      locale?: string): null;
-  transform(
-      value: number|string|null|undefined, currencyCode?: string,
-      display?: 'code'|'symbol'|'symbol-narrow'|string|boolean, digitsInfo?: string,
-      locale?: string): string|null;
   transform(
       value: number|string|null|undefined, currencyCode: string = this._defaultCurrencyCode,
       display: 'code'|'symbol'|'symbol-narrow'|string|boolean = 'symbol', digitsInfo?: string,