feat(browser): Make fetch the default transport for offline (#11209)

Now we only have one included transport, this simplifies the vast
majority of use cases:

Before:
```ts
import { init, makeBrowserOfflineTransport, makeFetchTransport } from "@sentry/browser";

init({
  dsn: "__DSN__",
  transport: makeBrowserOfflineTransport(makeFetchTransport)
})
```

After:
```ts
import { init, makeBrowserOfflineTransport } from "@sentry/browser";

init({
  dsn: "__DSN__",
  transport: makeBrowserOfflineTransport()
})
```

packages/browser/src/transports/offline.ts

@@ -1,7 +1,8 @@
 import type { OfflineStore, OfflineTransportOptions } from '@sentry/core';
 import { makeOfflineTransport } from '@sentry/core';
-import type { Envelope, InternalBaseTransportOptions, Transport } from '@sentry/types';
+import type { BaseTransportOptions, Envelope, Transport } from '@sentry/types';
 import { parseEnvelope, serializeEnvelope } from '@sentry/utils';
+import { makeFetchTransport } from './fetch';
 
 // 'Store', 'promisifyRequest' and 'createStore' were originally copied from the 'idb-keyval' package before being
 // modified and simplified: https://github.com/jakearchibald/idb-keyval
@@ -141,8 +142,8 @@ function makeIndexedDbOfflineTransport<T>(
 /**
  * Creates a transport that uses IndexedDb to store events when offline.
  */
-export function makeBrowserOfflineTransport<T extends InternalBaseTransportOptions>(
-  createTransport: (options: T) => Transport,
+export function makeBrowserOfflineTransport<T extends BaseTransportOptions>(
+  createTransport: (options: T) => Transport = makeFetchTransport,
 ): (options: T & BrowserOfflineTransportOptions) => Transport {
   return makeIndexedDbOfflineTransport<T>(makeOfflineTransport(createTransport));
 }

packages/browser/src/transports/types.ts

@@ -1,10 +1,6 @@
 import type { BaseTransportOptions } from '@sentry/types';
 
-import type { BrowserOfflineTransportOptions } from './offline';
-
-type BaseTransportAndOfflineTransportOptions = BaseTransportOptions & BrowserOfflineTransportOptions;
-
-export interface BrowserTransportOptions extends BaseTransportAndOfflineTransportOptions {
+export interface BrowserTransportOptions extends BaseTransportOptions {
   /** Fetch API init parameters. Used by the FetchTransport */
   fetchOptions?: RequestInit;
   /** Custom headers for the transport. Used by the XHRTransport and FetchTransport */

packages/browser/test/unit/transports/offline.test.ts

@@ -89,6 +89,7 @@ describe('makeOfflineTransport', () => {
         queuedCount += 1;
         return true;
       },
+      url: 'http://localhost',
     });
     const result = await transport.send(ERROR_ENVELOPE);