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

chrome/android/java/src/org/chromium/chrome/browser/WarmupManager.java

Index: chrome/android/java/src/org/chromium/chrome/browser/WarmupManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/WarmupManager.java b/chrome/android/java/src/org/chromium/chrome/browser/WarmupManager.java
index 3f4d6994c884318d725fc9a15a3758741a7bb5fb..1ed116eb2b8235e193a87867445b20610e01cfb5 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/WarmupManager.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/WarmupManager.java
@@ -15,13 +15,11 @@
 import android.widget.FrameLayout;
 
 import org.chromium.base.Log;
-import org.chromium.base.SysUtils;
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.TraceEvent;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.net.spdyproxy.DataReductionProxySettings;
 import org.chromium.chrome.browser.profiles.Profile;
-import org.chromium.content_public.browser.WebContents;
 
 import java.net.InetAddress;
 import java.net.MalformedURLException;
@@ -48,7 +46,6 @@
 
     private int mToolbarContainerId;
     private ViewGroup mMainView;
-    private WebContents mSpareWebContents;
 
     /**
      * @return The singleton instance for the WarmupManager, creating one if necessary.
@@ -195,50 +192,5 @@
         }
     }
 
-    /**
-     * Creates and initializes a spare WebContents, to be used in a subsequent navigation.
-     *
-     * This creates a renderer that is suitable for any navigation. It can be picked up by any tab.
-     * Can be called multiple times, and must be called from the UI thread.
-     * Note that this is a no-op on low-end devices.
-     */
-    public void createSpareWebContents() {
-        ThreadUtils.assertOnUiThread();
-        if (mSpareWebContents != null || SysUtils.isLowEndDevice()) return;
-        mSpareWebContents = WebContentsFactory.createWebContentsWithWarmRenderer(false, false);
-    }
-
-    /**
-     * Destroys the spare WebContents if there is one.
-     */
-    public void destroySpareWebContents() {
-        ThreadUtils.assertOnUiThread();
-        if (mSpareWebContents == null) return;
-        mSpareWebContents.destroy();
-        mSpareWebContents = null;
-    }
-
-    /**
-     * Returns a spare WebContents or null, depending on the availability of one.
-     *
-     * The parameters are the same as for {@link WebContentsFactory#createWebContents()}.
-     *
-     * @return a WebContents, or null.
-     */
-    public WebContents takeSpareWebContents(boolean incognito, boolean initiallyHidden) {
-        ThreadUtils.assertOnUiThread();
-        if (incognito || initiallyHidden) return null;
-        WebContents result = mSpareWebContents;
-        mSpareWebContents = null;
-        return result;
-    }
-
-    /**
-     * @return Whether a spare renderer is available.
-     */
-    public boolean hasSpareWebContents() {
-        return mSpareWebContents != null;
-    }
-
     private static native void nativePreconnectUrlAndSubresources(Profile profile, String url);
 }