fix(http): use params without RequestOptions (#14101)

`params` has been introduced in 4.0.0-beta.0

Before:

    http.get(url, new RequestOptions({params: searchParams}))

After:

    http.get(url, {params: searchParams})

Fixes #14100

PR Close #14101

modules/@angular/http/src/http.ts

@@ -28,6 +28,7 @@ function mergeOptions(
       method: providedOpts.method || method,
       url: providedOpts.url || url,
       search: providedOpts.search,
+      params: providedOpts.params,
       headers: providedOpts.headers,
       body: providedOpts.body,
       withCredentials: providedOpts.withCredentials,

modules/@angular/http/test/http_spec.ts

@@ -353,7 +353,6 @@ export function main() {
                  .subscribe((res: Response) => {});
            }));
 
-
         it('should append string search params to url',
            inject([AsyncTestCompleter], (async: AsyncTestCompleter) => {
              backend.connections.subscribe((c: MockConnection) => {
@@ -365,7 +364,6 @@ export function main() {
                  .subscribe((res: Response) => {});
            }));
 
-
         it('should produce valid url when url already contains a query',
            inject([AsyncTestCompleter], (async: AsyncTestCompleter) => {
              backend.connections.subscribe((c: MockConnection) => {
@@ -378,6 +376,19 @@ export function main() {
            }));
       });
 
+      describe('params', () => {
+        it('should append params to url',
+           inject([AsyncTestCompleter], (async: AsyncTestCompleter) => {
+             backend.connections.subscribe((c: MockConnection) => {
+               expect(c.request.url).toEqual('https://www.google.com?q=puppies');
+               backend.resolveAllConnections();
+               async.done();
+             });
+             http.get('https://www.google.com', {params: {q: 'puppies'}})
+                 .subscribe((res: Response) => {});
+           }));
+      });
+
       describe('string method names', () => {
         it('should allow case insensitive strings for method names', () => {
           inject([AsyncTestCompleter], (async: AsyncTestCompleter) => {