CustomTabs: Base version for prerender switch

chrome/android/java/src/org/chromium/chrome/browser/customtabs/ClientManager.java

Index: chrome/android/java/src/org/chromium/chrome/browser/customtabs/ClientManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/customtabs/ClientManager.java b/chrome/android/java/src/org/chromium/chrome/browser/customtabs/ClientManager.java
index 212f0ef590ac27fc24a108704e65a6e4995cdbff..1117a17c47ee93010c85c0f3dc98dce8540d0741 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/customtabs/ClientManager.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/customtabs/ClientManager.java
@@ -131,6 +131,7 @@ class ClientManager {
         private KeepAliveServiceConnection mKeepAliveConnection;
         private String mPredictedUrl;
         private long mLastMayLaunchUrlTimestamp;
+        private int mSpeculationMode;
 
         public SessionParams(Context context, int uid, DisconnectCallback callback,
                 PostMessageHandler postMessageHandler) {
@@ -138,6 +139,7 @@ class ClientManager {
             packageName = getPackageName(context, uid);
             disconnectCallback = callback;
             this.postMessageHandler = postMessageHandler;
+            this.mSpeculationMode = CustomTabsConnection.SpeculationParams.PRERENDER;
         }
 
         private static String getPackageName(Context context, int uid) {
@@ -450,6 +452,21 @@ class ClientManager {
         if (params != null) params.mShouldPrerenderOnCellular = prerender;
     }
 
+    /**
+     * Sets the speculation mode to be used by default for given session.
+     */
+    public synchronized void setSpeculationModeForSession(
+            CustomTabsSessionToken session, int speculationMode) {
+        SessionParams params = mSessionParams.get(session);
+        if (params != null) params.mSpeculationMode = speculationMode;
+    }
+
+    public synchronized int getSpeculationModeForSession(CustomTabsSessionToken session) {

[Benoit L, 2017/03/27 13:18:14]

tiny nit: I'm usually all for not adding javadoc to simple accessor, but in this
case can you document that the default returned value is PRERENDER?

[ahemery1, 2017/03/27 14:47:33]

Done.

+        SessionParams params = mSessionParams.get(session);
+        return params == null ? CustomTabsConnection.SpeculationParams.PRERENDER
+                              : params.mSpeculationMode;
+    }
+
     /** Tries to bind to a client to keep it alive, and returns true for success. */
     public synchronized boolean keepAliveForSession(CustomTabsSessionToken session, Intent intent) {
         // When an application is bound to a service, its priority is raised to