Add Data Saver support to Cronet

components/cronet/android/test/javatests/src/org/chromium/net/CronetUrlRequestContextTest.java

Index: components/cronet/android/test/javatests/src/org/chromium/net/CronetUrlRequestContextTest.java
diff --git a/components/cronet/android/test/javatests/src/org/chromium/net/CronetUrlRequestContextTest.java b/components/cronet/android/test/javatests/src/org/chromium/net/CronetUrlRequestContextTest.java
index b74554520b83b940556ad479154f3a2af83a136c..94b173868a8ee88941c05d3376a0116713a02ef0 100644
--- a/components/cronet/android/test/javatests/src/org/chromium/net/CronetUrlRequestContextTest.java
+++ b/components/cronet/android/test/javatests/src/org/chromium/net/CronetUrlRequestContextTest.java
@@ -122,6 +122,45 @@ public class CronetUrlRequestContextTest extends CronetTestBase {
 
     @SmallTest
     @Feature({"Cronet"})
+    public void testDataReductionProxyEnabled() throws Exception {
+        UrlRequestContextConfig config = new UrlRequestContextConfig();
+        config.enableDataReductionProxy(false, "test-key");
+        config.setLibraryName("cronet_tests");
+        String[] commandLineArgs = {
+                CronetTestActivity.CONFIG_KEY, config.toString()
+        };
+        mActivity = launchCronetTestAppWithUrlAndCommandLineArgs(null,
+                commandLineArgs);
+        assertTrue(NativeTestServer.startNativeTestServer(
+                getInstrumentation().getTargetContext()));
+
+        String serverHostPort = "127.0.0.1:" + NativeTestServer.getPort();

[mmenke, 2015/04/01 16:48:53]

Can we just use getHostPortPair instead of getPort?  Seems weird to grab just
the port of a URL with a host, and then re-attach the port to it later.

[bengr, 2015/04/24 02:30:43]

NativeTestServer doesn't hold onto the host.

[mmenke, 2015/04/24 15:54:59]

It does.  That's how the other NativeTestServer methods pull full URLs from it. 

In the cc file, use HostPortPair::FromURL(g_test_server->base_url()).ToString();

[bengr, 2015/04/24 21:13:50]

Done.

+        // Shutdown the original context and create a new context that uses the
+        // NativeTestServer as the data reduction proxy.
+        mActivity.mUrlRequestContext.shutdown();

[mmenke, 2015/04/01 16:48:53]

Why can't we just start the test server first, and enable the DRP the first
time?

[bengr, 2015/04/24 02:30:43]

This was a chicken and egg problem. The server needed a context, but we couldn't
configure the DRP until we got the port from the server.

[mmenke, 2015/04/24 15:54:59]

See skipFactoryInitInOnCreate.

+        UrlRequestContextConfig config2 = new UrlRequestContextConfig();
+        config2.enableDataReductionProxy(true, "test-key");
+        config2.setDataReductionProxyOptions(
+                serverHostPort + ","
+                + "unused.net:9999" + ","
+                + NativeTestServer.getFileURL("/secureproxychecksuccess.txt"));
+        config2.setLibraryName("cronet_tests");
+        mActivity.mUrlRequestContext =
+                mActivity.mUrlRequestContext.createContext(
+                        getInstrumentation().getTargetContext(), config2);
+        TestUrlRequestListener listener = new TestUrlRequestListener();
+        UrlRequest urlRequest = mActivity.mUrlRequestContext.createRequest(
+                "http://google.com/datareductionproxysuccess.txt",
+                listener, listener.getExecutor());
+
+        urlRequest.start();
+        listener.blockForDone();
+        assertEquals(200, listener.mResponseInfo.getHttpStatusCode());
+        assertEquals(serverHostPort, listener.mResponseInfo.getProxyServer());

[mmenke, 2015/04/01 16:48:53]

Should we check that the other parameters work as well?  Also, do we use the DRP
before we've gotten a response from the check URL?  Just wondering if there's a
chance we'll racily use a direct connection here while waiting for the probe
result.

[mmenke, 2015/04/01 16:48:53]

Check the URL as well?  (http://google.com/datareductionproxysuccess.txt).

[bengr, 2015/04/24 02:30:43]

What other parameters? The race doesn't matter. The secure proxy check tells
cronet to use the primary proxy, and the primary proxy is used until cronet gets
the response from the check.

[bengr, 2015/04/24 02:30:43]

Done.

[mmenke, 2015/04/24 15:54:59]

Other parameters -> The second proxy and the proxy check URL.

Ahh, I didn't realize that default behavior was to just use the DRP.  Had
thought we didn't use it until after the probe.

[bengr, 2015/04/24 21:13:50]

These aren't exposed easily. setDataReductionProxyOptions is for test only to
override default settings. The test would fail if the overrides didn't work.

+    }
+
+    @SmallTest
+    @Feature({"Cronet"})
     public void testShutdown() throws Exception {
         mActivity = launchCronetTestApp();
         TestUrlRequestListener listener = new ShutdownTestUrlRequestListener();