Refactor TabContentManager to async create ThumbnailCache.

chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/content/TabContentManager.java

Index: chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/content/TabContentManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/content/TabContentManager.java b/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/content/TabContentManager.java
index 0d14ddee919f809d359ed9605e35452b0abed363..4db041fd0b61be09bd2825ac942458c588d936fd 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/content/TabContentManager.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/content/TabContentManager.java
@@ -7,6 +7,7 @@ package org.chromium.chrome.browser.compositor.layouts.content;
 import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
+import android.os.AsyncTask;
 import android.util.SparseArray;
 import android.view.View;
 
@@ -24,6 +25,7 @@ import org.chromium.ui.base.DeviceFormFactor;
 import java.io.File;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.ExecutionException;
 
 /**
  * The TabContentManager is responsible for serving tab contents to the UI components. Contents
@@ -33,10 +35,11 @@ import java.util.List;
 public class TabContentManager {
     private static final String THUMBNAIL_DIRECTORY = "textures";
     private final Context mContext;
-    private final File mThumbnailsDir;
-    private final float mThumbnailScale;
-    private final int mFullResThumbnailsMaxSize;
     private final ContentOffsetProvider mContentOffsetProvider;
+
+    private File mThumbnailsDir;
+    private float mThumbnailScale;
+    private int mFullResThumbnailsMaxSize;
     private int[] mPriorityTabIds;
     private long mNativeTabContentManager;
 
@@ -57,6 +60,7 @@ public class TabContentManager {
             new SparseArray<TabContentManager.DecompressThumbnailCallback>();
 
     private boolean mSnapshotsEnabled;
+    private AsyncTask<Void, Void, Void> mNativeThumbnailCacheInitTask;
 
     /**
      * The Java interface for listening to thumbnail changes.
@@ -96,48 +100,59 @@ public class TabContentManager {
         mContentOffsetProvider = contentOffsetProvider;
         mSnapshotsEnabled = snapshotsEnabled;
 
-        mThumbnailsDir = mContext.getDir(THUMBNAIL_DIRECTORY, Context.MODE_PRIVATE);
-        String diskCachePath = mThumbnailsDir.getAbsolutePath();
-
-        // Override the cache size on the command line with --thumbnails=100
-        int defaultCacheSize = getIntegerResourceWithOverride(mContext,
-                R.integer.default_thumbnail_cache_size, ChromeSwitches.THUMBNAILS);
-
-        mFullResThumbnailsMaxSize = defaultCacheSize;
-
-        int compressionQueueMaxSize = mContext.getResources().getInteger(
-                R.integer.default_compression_queue_size);
-        int writeQueueMaxSize = mContext.getResources().getInteger(
-                R.integer.default_write_queue_size);
-
-        // Override the cache size on the command line with
-        // --approximation-thumbnails=100
-        int approximationCacheSize = getIntegerResourceWithOverride(mContext,
-                R.integer.default_approximation_thumbnail_cache_size,
-                ChromeSwitches.APPROXIMATION_THUMBNAILS);
-
-        float thumbnailScale = 1.f;
-        boolean useApproximationThumbnails;
-        float deviceDensity = mContext.getResources().getDisplayMetrics().density;
-        if (DeviceFormFactor.isTablet(mContext)) {
-            // Scale all tablets to MDPI.
-            thumbnailScale = 1.f / deviceDensity;
-            useApproximationThumbnails = false;
-        } else {
-            // For phones, reduce the amount of memory usage by capturing a lower-res thumbnail for
-            // devices with resolution higher than HDPI (crbug.com/357740).
-            if (deviceDensity > 1.5f) {
-                thumbnailScale = 1.5f / deviceDensity;
-            }
-            useApproximationThumbnails = true;
-        }
-        mThumbnailScale = thumbnailScale;
+        mNativeTabContentManager = nativeInit();
+
+        mNativeThumbnailCacheInitTask = new AsyncTask<Void, Void, Void>() {
+            @Override
+            protected Void doInBackground(Void... unused) {
+                mThumbnailsDir = mContext.getDir(THUMBNAIL_DIRECTORY, Context.MODE_PRIVATE);
+                String diskCachePath = mThumbnailsDir.getAbsolutePath();
+
+                // Override the cache size on the command line with --thumbnails=100
+                int defaultCacheSize = getIntegerResourceWithOverride(mContext,
+                        R.integer.default_thumbnail_cache_size, ChromeSwitches.THUMBNAILS);
+
+                mFullResThumbnailsMaxSize = defaultCacheSize;
+
+                int compressionQueueMaxSize = mContext.getResources().getInteger(
+                        R.integer.default_compression_queue_size);
+                int writeQueueMaxSize = mContext.getResources().getInteger(
+                        R.integer.default_write_queue_size);
+
+                // Override the cache size on the command line with
+                // --approximation-thumbnails=100
+                int approximationCacheSize = getIntegerResourceWithOverride(mContext,
+                        R.integer.default_approximation_thumbnail_cache_size,
+                        ChromeSwitches.APPROXIMATION_THUMBNAILS);
+
+                float thumbnailScale = 1.f;
+                boolean useApproximationThumbnails;
+                float deviceDensity = mContext.getResources().getDisplayMetrics().density;
+                if (DeviceFormFactor.isTablet(mContext)) {
+                    // Scale all tablets to MDPI.
+                    thumbnailScale = 1.f / deviceDensity;
+                    useApproximationThumbnails = false;
+                } else {
+                    // For phones, reduce the amount of memory usage by capturing a lower-res
+                    // thumbnail for devices with resolution higher than HDPI (crbug.com/357740).
+                    if (deviceDensity > 1.5f) {
+                        thumbnailScale = 1.5f / deviceDensity;
+                    }
+                    useApproximationThumbnails = true;
+                }
+                mThumbnailScale = thumbnailScale;
+
+                mPriorityTabIds = new int[mFullResThumbnailsMaxSize];
 
-        mPriorityTabIds = new int[mFullResThumbnailsMaxSize];
+                if (mNativeTabContentManager != 0) {
+                    nativeCreateThumbnailCache(mNativeTabContentManager, diskCachePath,

[David Trainor- moved to gerrit, 2015/05/07 17:57:35]

This doesn't look thread safe.  What if someone calls destroy() on this
TabContentManager in between the != 0 and the nativeCreateThumbnailCache call?

[Peter Wen, 2015/05/07 22:08:10]

Done.

+                            defaultCacheSize, approximationCacheSize, compressionQueueMaxSize,
+                            writeQueueMaxSize, useApproximationThumbnails);
+                }
 
-        mNativeTabContentManager = nativeInit(diskCachePath, defaultCacheSize,
-                approximationCacheSize, compressionQueueMaxSize, writeQueueMaxSize,
-                useApproximationThumbnails);
+                return null;
+            }
+        }.executeOnExecutor(AsyncTask.SERIAL_EXECUTOR);
     }
 
     /**
@@ -151,6 +166,15 @@ public class TabContentManager {
     }
 
     @CalledByNative
+    private void blockOnThumbnailCacheCreation() {
+        try {
+            mNativeThumbnailCacheInitTask.get();
+        } catch (InterruptedException e) {
+        } catch (ExecutionException e) {
+        }
+    }
+
+    @CalledByNative
     private long getNativePtr() {
         return mNativeTabContentManager;
     }
@@ -331,8 +355,10 @@ public class TabContentManager {
      * @param modelSelector The selector that answers whether a tab is currently present.
      */
     public void cleanupPersistentData(TabModelSelector modelSelector) {
+        if (mNativeTabContentManager == 0) return;
+
         File[] files = mThumbnailsDir.listFiles();
-        if (files == null || mNativeTabContentManager == 0) return;
+        if (files == null) return;
 
         for (File file : files) {
             try {
@@ -365,9 +391,10 @@ public class TabContentManager {
     }
 
     // Class Object Methods
-    private native long nativeInit(String diskCachePath, int defaultCacheSize,
-            int approximationCacheSize, int compressionQueueMaxSize, int writeQueueMaxSize,
-            boolean useApproximationThumbnail);
+    private native long nativeInit();
+    private native void nativeCreateThumbnailCache(long nativeTabContentManager,
+            String diskCachePath, int defaultCacheSize, int approximationCacheSize,
+            int compressionQueueMaxSize, int writeQueueMaxSize, boolean useApproximationThumbnail);
     private native boolean nativeHasFullCachedThumbnail(long nativeTabContentManager, int tabId);
     private native void nativeCacheTab(long nativeTabContentManager, Object tab,
             Object contentViewCore, float thumbnailScale);