Revert of Android: Make the spare renderer accessible to all Chrome tabs.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabActivity.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabActivity.java
index 594f725d26974ff7825645b23c54206fa3d9a999..48bcfcf6290fb332c35f52e07806ffc7c6fa28d6 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabActivity.java
@@ -38,7 +38,6 @@
 import org.chromium.chrome.browser.IntentHandler;
 import org.chromium.chrome.browser.IntentHandler.ExternalAppId;
 import org.chromium.chrome.browser.KeyboardShortcuts;
-import org.chromium.chrome.browser.WarmupManager;
 import org.chromium.chrome.browser.WebContentsFactory;
 import org.chromium.chrome.browser.appmenu.AppMenuPropertiesDelegate;
 import org.chromium.chrome.browser.compositor.layouts.LayoutManagerDocument;
@@ -93,12 +92,10 @@
 
     private boolean mHasCreatedTabEarly;
     private boolean mIsInitialStart = true;
-    // Whether there is any prerender associated with the session.
     private boolean mHasPrerender;
     private CustomTabObserver mTabObserver;
 
     private String mPrerenderedUrl;
-    // Whether a prerender is being used.
     private boolean mHasPrerendered;
 
     private static class PageLoadMetricsObserver implements PageLoadMetrics.Observer {
@@ -252,8 +249,7 @@
 
     @Override
     public boolean shouldAllocateChildConnection() {
-        return !mHasCreatedTabEarly && !mHasPrerender
-                && !WarmupManager.getInstance().hasSpareWebContents();
+        return !mHasCreatedTabEarly && !mHasPrerender;
     }
 
     @Override
@@ -415,9 +411,7 @@
         WebContents webContents =
                 customTabsConnection.takePrerenderedUrl(mSession, url, referrerUrl);
         mHasPrerendered = webContents != null;
-        if (!mHasPrerendered) {
-            webContents = WarmupManager.getInstance().takeSpareWebContents(false, false);
-        }
+        if (webContents == null) webContents = customTabsConnection.takeSpareWebContents();
         if (webContents == null) webContents = WebContentsFactory.createWebContents(false, false);
         tab.initialize(webContents, getTabContentManager(),
                 new CustomTabDelegateFactory(mIntentDataProvider.shouldEnableUrlBarHiding()), false,