<webview>: Implement declarativeWebRequest API

chrome/common/extensions/api/webview_request.json

Index: chrome/common/extensions/api/webview_request.json
diff --git a/chrome/common/extensions/api/webview_request.json b/chrome/common/extensions/api/webview_request.json
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+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+[
+  {
+    "namespace": "webViewRequest",
+    "description": "Use the <code>chrome.webViewRequest</code> API to intercept, block, or modify requests in-flight. It is significantly faster than the <a href='webRequest.html'><code>chrome.webRequest</code> API</a> because you can register rules that are evaluated in the browser rather than the JavaScript engine with reduces roundtrip latencies and allows higher efficiency."

[vabr (Chromium), 2013/10/25 20:40:24]

Maybe we should be careful with saying "significantly faster", unless we have
benchmarks to prove it. While speed was one of the main motivations for
introducing DWR, and it saves the round-trips, the difference might not be that
significant after all, due to recent improvements in V8 and other parts of
Chrome critical for WebRequest.

There is still a good incentive to use DWR as opposed to the old WR: declarative
programming in general is a good practice to avoid boilerplate in the
extensions, content scripts, and improve security. The security win is prominent
outside of webview, where certain more dangerous parts of DWR (redirecting as
opposed to just blocking) can be separated by higher permissions. This is
probably not so relevant for webview.

[Fady Samuel, 2013/10/25 22:48:08]

The original WebRequest requires more lines of code. The declarative WebRequest
API is more succinct in some cases I feel. The WebRequest API is used
extensively in <webview> and so the declarative WebRequest was requested. I will
soften the language to say it is potentially faster.

[vabr (Chromium), 2013/10/28 14:46:09]

Thanks, "potentially" sounds safer.

+  }
+]