Add HTTP cache by default (like iOS) (facebook#18348)

Summary:
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On iOS, the cache is enabled by default but it's not the case on Android. This PR adds 10Mo of HTTP cache by default. 10Mo was chosen arbitrarily.

Fixes facebook#16795

<!--(Write your test plan here. If you changed any code, please provide us with clear instructions on how you verified your changes work. Bonus points for screenshots and videos!)-->

I wrote it so there's no breaking change for those already using the `OkHttpClientProvider.createClient` and `OkHttpClientProvider.createClientBuilder` public methods.

1. react-native init TestAndroidCache
2. Followed https://facebook.github.io/react-native/docs/android-building-from-source.html to build  with this branch as react-native
3. Added the following code in the App.js (with correct URL_WITH_CACHE_CONTROL)
4. Made sure the debugger is closed
5. Throttled my mac's network speed with the `Network link conditioner` (edge)
6. Tapped "Fetch", it shows ~4000
7. Tapped "Fetch" again, it shows ~6

```js
import React, { Component } from 'react';
import {
  StyleSheet,
  Alert,
  View,
  Button
} from 'react-native';

type Props = {};
export default class App extends Component<Props> {
  fetch = () => {
    const start = Date.now();
    fetch('{URL_WITH_CACHE_CONTROL}').then(() => {
      const diff = Date.now() - start;
      Alert.alert(diff.toString());
    });
  };

  render() {
    return (
      <View style={styles.container}>
        <Button title={"fetch"} onPress={this.fetch} />
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: '#F5FCFF',
  },
});
```

None

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  CATEGORY
[----------]        TYPE
[ CLI      ]   [-------------]      LOCATION
[ DOCS     ]   [ BREAKING    ]   [-------------]
[ GENERAL  ]   [ BUGFIX      ]   [-{Component}-]
[ INTERNAL ]   [ ENHANCEMENT ]   [ {File}      ]
[ IOS      ]   [ FEATURE     ]   [ {Directory} ]   |-----------|
[ ANDROID  ]   [ MINOR       ]   [ {Framework} ] - | {Message} |
[----------]   [-------------]   [-------------]   |-----------|

[CATEGORY] [TYPE] [LOCATION] - MESSAGE

 EXAMPLES:

 [IOS] [BREAKING] [FlatList] - Change a thing that breaks other things
 [ANDROID] [BUGFIX] [TextInput] - Did a thing to TextInput
 [CLI] [FEATURE] [local-cli/info/info.js] - CLI easier to do things with
 [DOCS] [BUGFIX] [GettingStarted.md] - Accidentally a thing/word
 [GENERAL] [ENHANCEMENT] [Yoga] - Added new yoga thing/position
 [INTERNAL] [FEATURE] [./scripts] - Added thing to script that nobody will see
-->
[ANDROID] [FEATURE] [Networking] Add HTTP caching
Pull Request resolved: facebook#18348

Differential Revision: D13680430

Pulled By: hramos

fbshipit-source-id: 1e49cf75702db72b20a316e9cdd971605f8fe7e0

ReactAndroid/src/main/java/com/facebook/react/modules/network/NetworkingModule.java

@@ -163,7 +163,7 @@ public interface ResponseHandler {
    * @param context the ReactContext of the application
    */
   public NetworkingModule(final ReactApplicationContext context) {
-    this(context, null, OkHttpClientProvider.createClient(), null);
+    this(context, null, OkHttpClientProvider.createClient(context), null);
   }
 
   /**
@@ -174,7 +174,7 @@ public NetworkingModule(final ReactApplicationContext context) {
   public NetworkingModule(
     ReactApplicationContext context,
     List<NetworkInterceptorCreator> networkInterceptorCreators) {
-    this(context, null, OkHttpClientProvider.createClient(), networkInterceptorCreators);
+    this(context, null, OkHttpClientProvider.createClient(context), networkInterceptorCreators);
   }
 
   /**
@@ -183,7 +183,7 @@ public NetworkingModule(
    * caller does not provide one explicitly
    */
   public NetworkingModule(ReactApplicationContext context, String defaultUserAgent) {
-    this(context, defaultUserAgent, OkHttpClientProvider.createClient(), null);
+    this(context, defaultUserAgent, OkHttpClientProvider.createClient(context), null);
   }
 
   @Override

ReactAndroid/src/main/java/com/facebook/react/modules/network/OkHttpClientProvider.java

@@ -7,16 +7,19 @@
 
 package com.facebook.react.modules.network;
 
+import android.content.Context;
 import android.os.Build;
 
 import com.facebook.common.logging.FLog;
 
+import java.io.File;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 
 import javax.annotation.Nullable;
 
+import okhttp3.Cache;
 import okhttp3.ConnectionSpec;
 import okhttp3.OkHttpClient;
 import okhttp3.TlsVersion;
@@ -57,6 +60,13 @@ public static OkHttpClient createClient() {
     return createClientBuilder().build();
   }
 
+  public static OkHttpClient createClient(Context context) {
+    if (sFactory != null) {
+      return sFactory.createNewNetworkModuleClient();
+    }
+    return createClientBuilder(context).build();
+  }
+
   public static OkHttpClient.Builder createClientBuilder() {
     // No timeouts by default
     OkHttpClient.Builder client = new OkHttpClient.Builder()
@@ -68,6 +78,24 @@ public static OkHttpClient.Builder createClientBuilder() {
     return enableTls12OnPreLollipop(client);
   }
 
+  public static OkHttpClient.Builder createClientBuilder(Context context) {
+    int cacheSize = 10 * 1024 * 1024; // 10 Mo
+    return createClientBuilder(context, cacheSize);
+  }
+
+  public static OkHttpClient.Builder createClientBuilder(Context context, int cacheSize) {
+    OkHttpClient.Builder client = createClientBuilder();
+
+    if (cacheSize == 0) {
+      return client;
+    }
+
+    File cacheDirectory = new File(context.getCacheDir(), "http-cache");
+    Cache cache = new Cache(cacheDirectory, cacheSize);
+
+    return client.cache(cache);
+  }
+
   /*
     On Android 4.1-4.4 (API level 16 to 19) TLS 1.1 and 1.2 are
     available but not enabled by default. The following method