Remove redundant serviceworker/cache-* tests

LayoutTests/http/tests/serviceworker/resources/cache-delete-worker.js

-importScripts('worker-testharness.js');
-importScripts('/resources/testharness-helpers.js');
-
-var test_url = 'https://example.com/foo';
-
-// Construct a generic Request object. The URL is |test_url|. All other fields
-// are defaults.
-function new_test_request() {
-  return new Request(test_url);
-}
-
-// Construct a generic Response object.
-function new_test_response() {
-  return new Response('Hello world!', { status: 200 });
-}
-
-cache_test(function(cache) {
-    return assert_promise_rejects(
-      cache.delete(),
-      new TypeError(),
-      'Cache.delete should reject with a TypeError when called with no ' +
-      'arguments.');
-  }, 'Cache.delete with no arguments');
-
-cache_test(function(cache) {
-    return cache.put(new_test_request(), new_test_response())
-      .then(function() {
-          return cache.delete(test_url);
-        })
-      .then(function(result) {
-          assert_true(result,
-                      'Cache.delete should resolve with "true" if an entry ' +
-                      'was successfully deleted.');
-        })
-      .then(function() {
-          assert_promise_rejects(
-            cache.match(test_url),
-            'NotFoundError',
-            'Cache.delete should remove matching entries from cache.');
-        });
-  }, 'Cache.delete called with a string URL');
-
-cache_test(function(cache) {
-    var request = new Request(test_url, { method: 'POST', body: 'Abc' });
-    return cache.put(request.clone(), new_test_response())
-      .then(function() {
-          return cache.delete(request);
-        })
-      .then(function(result) {
-          assert_true(result,
-                      'Cache.delete should resolve with "true" if an entry ' +
-                      'was successfully deleted.');
-          assert_false(request.bodyUsed,
-                       'Cache.delete should not consume request body.');
-        });
-  }, 'Cache.delete called with a Request object');
-
-cache_test(function(cache) {
-    var request = new Request(test_url, { method: 'POST', body: 'Abc' });
-    return cache.put(request.clone(), new_test_response())
-      .then(function() {
-          return request.text();
-        })
-      .then(function() {
-          assert_true(request.bodyUsed,
-                      '[https://fetch.spec.whatwg.org/#body-mixin] ' +
-                      'Request.bodyUsed should be true after text() method ' +
-                      'resolves.');
-        })
-      .then(function() {
-          return cache.delete(request);
-        })
-      .then(function(result) {
-          assert_true(result,
-                      'Cache.delete should resolve with "true" if an entry ' +
-                      'was successfully deleted.');
-        });
-  }, 'Cache.delete with a Request object containing used body');
-
-cache_test(function(cache) {
-    return cache.delete(test_url)
-      .then(function(result) {
-          assert_false(result,
-                       'Cache.delete should resolve with "false" if there ' +
-                       'are no matching entries.');
-        });
-  }, 'Cache.delete with a non-existent entry');
-
-var cache_entries = {
-  a: {
-    request: new Request('http://example.com/abc'),
-    response: new Response('')
-  },
-
-  b: {
-    request: new Request('http://example.com/b'),
-    response: new Response('')
-  },
-
-  a_with_query: {
-    request: new Request('http://example.com/abc?q=r'),
-    response: new Response('')
-  }
-};
-
-function prepopulated_cache_test(test_function, description) {
-  cache_test(function(cache) {
-      return Promise.all(Object.keys(cache_entries).map(function(k) {
-          return cache.put(cache_entries[k].request.clone(),
-                           cache_entries[k].response.clone());
-        }))
-        .then(function() {
-            return test_function(cache);
-          });
-    }, description);
-}