Reland "Move Java CachedMetrics functionality to base/."

This is a re-land of:
https://codereview.chromium.org/2435813002/

The reland keeps a TimesHistogramSample class in LaunchMetrics
since it's still referenced in internal code. Once this lands, the
clank/ code can be updated and this class can be cleaned up.

Original CL description:

This is general-purpose functionality that allows
recording UMA metrics before the C++ native library
has been loaded and is useful to have outside of the
Chrome layer. In particular, I will be using it from
components/variations to record information about the
first run variations seed fetch.

No functional changes in this CL.

BUG=632199
TBR=bauerb@chromium.org, thestig@chromium.org

Review-Url: https://chromiumcodereview.appspot.com/2439113002
Cr-Commit-Position: refs/heads/master@{#426853}

base/BUILD.gn

@@ -2322,6 +2322,7 @@ if (is_android) {
       "android/java/src/org/chromium/base/library_loader/ModernLinker.java",
       "android/java/src/org/chromium/base/library_loader/NativeLibraryPreloader.java",
       "android/java/src/org/chromium/base/library_loader/ProcessInitException.java",
+      "android/java/src/org/chromium/base/metrics/CachedMetrics.java",
       "android/java/src/org/chromium/base/metrics/RecordHistogram.java",
       "android/java/src/org/chromium/base/metrics/RecordUserAction.java",
       "android/java/src/org/chromium/base/metrics/StatisticsRecorderAndroid.java",

base/android/java/src/org/chromium/base/metrics/CachedMetrics.java

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.base.metrics;
+
+import org.chromium.base.library_loader.LibraryLoader;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Utility classes for recording UMA metrics before the native library
+ * may have been loaded.  Metrics are cached until the library is known
+ * to be loaded, then committed to the MetricsService all at once.
+ */
+public class CachedMetrics {
+    /**
+     * Creating an instance of a subclass of this class automatically adds it to a list of objects
+     * that are committed when the native library is available.
+     */
+    private abstract static class CachedHistogram {
+        private static final List<CachedHistogram> sEvents = new ArrayList<CachedHistogram>();
+
+        protected final String mHistogramName;
+
+        /**
+         * @param histogramName Name of the histogram to record.
+         */
+        protected CachedHistogram(String histogramName) {
+            mHistogramName = histogramName;
+            sEvents.add(this);
+        }
+
+        /** Commits the histogram. Expects the native library to be loaded. */
+        protected abstract void commitAndClear();
+    }
+
+    /**
+     * Caches an action that will be recorded after native side is loaded.
+     */
+    public static class ActionEvent extends CachedHistogram {
+        private int mCount;
+
+        public ActionEvent(String actionName) {
+            super(actionName);
+        }
+
+        public void record() {
+            if (LibraryLoader.isInitialized()) {
+                recordWithNative();
+            } else {
+                mCount++;
+            }
+        }
+
+        private void recordWithNative() {
+            RecordUserAction.record(mHistogramName);
+        }
+
+        @Override
+        protected void commitAndClear() {
+            while (mCount > 0) {
+                recordWithNative();
+                mCount--;
+            }
+        }
+    }
+
+    /** Caches a set of integer histogram samples. */
+    public static class SparseHistogramSample extends CachedHistogram {
+        private final List<Integer> mSamples = new ArrayList<Integer>();
+
+        public SparseHistogramSample(String histogramName) {
+            super(histogramName);
+        }
+
+        public void record(int sample) {
+            if (LibraryLoader.isInitialized()) {
+                recordWithNative(sample);
+            } else {
+                mSamples.add(sample);
+            }
+        }
+
+        private void recordWithNative(int sample) {
+            RecordHistogram.recordSparseSlowlyHistogram(mHistogramName, sample);
+        }
+
+        @Override
+        protected void commitAndClear() {
+            for (Integer sample : mSamples) {
+                recordWithNative(sample);
+            }
+            mSamples.clear();
+        }
+    }
+
+    /** Caches a set of enumerated histogram samples. */
+    public static class EnumeratedHistogramSample extends CachedHistogram {
+        private final List<Integer> mSamples = new ArrayList<Integer>();
+        private final int mMaxValue;
+
+        public EnumeratedHistogramSample(String histogramName, int maxValue) {
+            super(histogramName);
+            mMaxValue = maxValue;
+        }
+
+        public void record(int sample) {
+            if (LibraryLoader.isInitialized()) {
+                recordWithNative(sample);
+            } else {
+                mSamples.add(sample);
+            }
+        }
+
+        private void recordWithNative(int sample) {
+            RecordHistogram.recordEnumeratedHistogram(mHistogramName, sample, mMaxValue);
+        }
+
+        @Override
+        protected void commitAndClear() {
+            for (Integer sample : mSamples) {
+                recordWithNative(sample);
+            }
+            mSamples.clear();
+        }
+    }
+
+    /** Caches a set of times histogram samples. */
+    public static class TimesHistogramSample extends CachedHistogram {
+        private final List<Long> mSamples = new ArrayList<Long>();
+        private final TimeUnit mTimeUnit;
+
+        public TimesHistogramSample(String histogramName, TimeUnit timeUnit) {
+            super(histogramName);
+            mTimeUnit = timeUnit;
+        }
+
+        public void record(long sample) {
+            if (LibraryLoader.isInitialized()) {
+                recordWithNative(sample);
+            } else {
+                mSamples.add(sample);
+            }
+        }
+
+        private void recordWithNative(long sample) {
+            RecordHistogram.recordTimesHistogram(mHistogramName, sample, mTimeUnit);
+        }
+
+        @Override
+        protected void commitAndClear() {
+            for (Long sample : mSamples) {
+                recordWithNative(sample);
+            }
+            mSamples.clear();
+        }
+    }
+
+    /**
+     * Calls out to native code to commit any cached histograms and events.
+     * Should be called once the native library has been loaded.
+     */
+    public static void commitCachedMetrics() {
+        for (CachedHistogram event : CachedHistogram.sEvents) event.commitAndClear();
+    }
+}

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

@@ -22,9 +22,9 @@ import android.widget.LinearLayout;
 import android.widget.RemoteViews;
 
 import org.chromium.base.Log;
+import org.chromium.base.metrics.CachedMetrics;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeActivity;
-import org.chromium.chrome.browser.metrics.LaunchMetrics;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.ui.interpolators.BakedBezierInterpolator;
 
@@ -35,10 +35,10 @@ import java.util.List;
  */
 class CustomTabBottomBarDelegate {
     private static final String TAG = "CustomTab";
-    private static final LaunchMetrics.ActionEvent REMOTE_VIEWS_SHOWN =
-            new LaunchMetrics.ActionEvent("CustomTabsRemoteViewsShown");
-    private static final LaunchMetrics.ActionEvent REMOTE_VIEWS_UPDATED =
-            new LaunchMetrics.ActionEvent("CustomTabsRemoteViewsUpdated");
+    private static final CachedMetrics.ActionEvent REMOTE_VIEWS_SHOWN =
+            new CachedMetrics.ActionEvent("CustomTabsRemoteViewsShown");
+    private static final CachedMetrics.ActionEvent REMOTE_VIEWS_UPDATED =
+            new CachedMetrics.ActionEvent("CustomTabsRemoteViewsUpdated");
     private static final int SLIDE_ANIMATION_DURATION_MS = 400;
     private ChromeActivity mActivity;
     private ViewGroup mBottomBarView;

chrome/android/java/src/org/chromium/chrome/browser/document/ChromeLauncherActivity.java

@@ -25,6 +25,7 @@ import org.chromium.base.CommandLineInitUtil;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.Log;
 import org.chromium.base.TraceEvent;
+import org.chromium.base.metrics.CachedMetrics;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeApplication;
 import org.chromium.chrome.browser.ChromeSwitches;
@@ -42,7 +43,6 @@ import org.chromium.chrome.browser.firstrun.FirstRunActivity;
 import org.chromium.chrome.browser.firstrun.FirstRunFlowSequencer;
 import org.chromium.chrome.browser.firstrun.LightweightFirstRunActivity;
 import org.chromium.chrome.browser.instantapps.InstantAppsHandler;
-import org.chromium.chrome.browser.metrics.LaunchMetrics;
 import org.chromium.chrome.browser.metrics.MediaNotificationUma;
 import org.chromium.chrome.browser.multiwindow.MultiWindowUtils;
 import org.chromium.chrome.browser.notifications.NotificationPlatformBridge;
@@ -87,8 +87,8 @@ public class ChromeLauncherActivity extends Activity
      */
     private static final int PARTNER_BROWSER_CUSTOMIZATIONS_TIMEOUT_MS = 10000;
 
-    private static final LaunchMetrics.SparseHistogramSample sIntentFlagsHistogram =
-            new LaunchMetrics.SparseHistogramSample("Launch.IntentFlags");
+    private static final CachedMetrics.SparseHistogramSample sIntentFlagsHistogram =
+            new CachedMetrics.SparseHistogramSample("Launch.IntentFlags");
 
     private IntentHandler mIntentHandler;
     private boolean mIsInLegacyMultiInstanceMode;

chrome/android/java/src/org/chromium/chrome/browser/externalauth/ExternalAuthUtils.java

@@ -21,9 +21,9 @@ import org.chromium.base.ContextUtils;
 import org.chromium.base.Log;
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.VisibleForTesting;
+import org.chromium.base.metrics.CachedMetrics.SparseHistogramSample;
+import org.chromium.base.metrics.CachedMetrics.TimesHistogramSample;
 import org.chromium.chrome.browser.ChromeApplication;
-import org.chromium.chrome.browser.metrics.LaunchMetrics.SparseHistogramSample;
-import org.chromium.chrome.browser.metrics.LaunchMetrics.TimesHistogramSample;
 
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicReference;

chrome/android/java/src/org/chromium/chrome/browser/externalauth/UserRecoverableErrorHandler.java

@@ -11,7 +11,7 @@ import android.content.Context;
 import com.google.android.gms.common.GoogleApiAvailability;
 
 import org.chromium.base.ThreadUtils;
-import org.chromium.chrome.browser.metrics.LaunchMetrics.EnumeratedHistogramSample;
+import org.chromium.base.metrics.CachedMetrics.EnumeratedHistogramSample;
 
 import java.util.concurrent.atomic.AtomicBoolean;
 

chrome/android/java/src/org/chromium/chrome/browser/instantapps/InstantAppsHandler.java

@@ -15,11 +15,11 @@ import org.chromium.base.CommandLine;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.FieldTrialList;
 import org.chromium.base.Log;
+import org.chromium.base.metrics.CachedMetrics.TimesHistogramSample;
 import org.chromium.chrome.browser.ChromeApplication;
 import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.IntentHandler;
 import org.chromium.chrome.browser.externalnav.ExternalNavigationDelegateImpl;
-import org.chromium.chrome.browser.metrics.LaunchMetrics.TimesHistogramSample;
 import org.chromium.chrome.browser.preferences.ChromePreferenceManager;
 import org.chromium.chrome.browser.util.IntentUtils;
 import org.chromium.content_public.browser.WebContents;

chrome/android/java/src/org/chromium/chrome/browser/metrics/LaunchMetrics.java

@@ -7,9 +7,7 @@ package org.chromium.chrome.browser.metrics;
 import android.util.Pair;
 
 import org.chromium.base.annotations.JNINamespace;
-import org.chromium.base.library_loader.LibraryLoader;
-import org.chromium.base.metrics.RecordHistogram;
-import org.chromium.base.metrics.RecordUserAction;
+import org.chromium.base.metrics.CachedMetrics;
 import org.chromium.content_public.browser.WebContents;
 
 import java.util.ArrayList;
@@ -23,147 +21,13 @@ import java.util.concurrent.TimeUnit;
  */
 @JNINamespace("metrics")
 public class LaunchMetrics {
-
-    /**
-     * Creating an instance of a subclass of this class automatically adds it to a list of objects
-     * that are committed when the native library is available.
-     */
-    private abstract static class CachedHistogram {
-        private static final List<CachedHistogram> sEvents = new ArrayList<CachedHistogram>();
-
-        protected final String mHistogramName;
-
-        /**
-         * @param histogramName Name of the histogram to record.
-         */
-        protected CachedHistogram(String histogramName) {
-            mHistogramName = histogramName;
-            sEvents.add(this);
-        }
-
-        /** Commits the histogram. Expects the native library to be loaded. */
-        protected abstract void commitAndClear();
-    }
-
     /**
-     * Caches an action that will be recorded after native side is loaded.
+     * Caches a set of times histogram samples.
+     * TODO(asvitkine): Remove after internal code is migrated to CachedMetrics.
      */
-    public static class ActionEvent extends CachedHistogram {
-        private int mCount;
-
-        public ActionEvent(String actionName) {
-            super(actionName);
-        }
-
-        public void record() {
-            if (LibraryLoader.isInitialized()) {
-                recordWithNative();
-            } else {
-                mCount++;
-            }
-        }
-
-        private void recordWithNative() {
-            RecordUserAction.record(mHistogramName);
-        }
-
-        @Override
-        protected void commitAndClear() {
-            while (mCount > 0) {
-                recordWithNative();
-                mCount--;
-            }
-        }
-    }
-
-    /** Caches a set of integer histogram samples. */
-    public static class SparseHistogramSample extends CachedHistogram {
-        private final List<Integer> mSamples = new ArrayList<Integer>();
-
-        public SparseHistogramSample(String histogramName) {
-            super(histogramName);
-        }
-
-        public void record(int sample) {
-            if (LibraryLoader.isInitialized()) {
-                recordWithNative(sample);
-            } else {
-                mSamples.add(sample);
-            }
-        }
-
-        private void recordWithNative(int sample) {
-            RecordHistogram.recordSparseSlowlyHistogram(mHistogramName, sample);
-        }
-
-        @Override
-        protected void commitAndClear() {
-            for (Integer sample : mSamples) {
-                recordWithNative(sample);
-            }
-            mSamples.clear();
-        }
-    }
-
-    /** Caches a set of enumerated histogram samples. */
-    public static class EnumeratedHistogramSample extends CachedHistogram {
-        private final List<Integer> mSamples = new ArrayList<Integer>();
-        private final int mMaxValue;
-
-        public EnumeratedHistogramSample(String histogramName, int maxValue) {
-            super(histogramName);
-            mMaxValue = maxValue;
-        }
-
-        public void record(int sample) {
-            if (LibraryLoader.isInitialized()) {
-                recordWithNative(sample);
-            } else {
-                mSamples.add(sample);
-            }
-        }
-
-        private void recordWithNative(int sample) {
-            RecordHistogram.recordEnumeratedHistogram(mHistogramName, sample, mMaxValue);
-        }
-
-        @Override
-        protected void commitAndClear() {
-            for (Integer sample : mSamples) {
-                recordWithNative(sample);
-            }
-            mSamples.clear();
-        }
-    }
-
-    /** Caches a set of times histogram samples. */
-    public static class TimesHistogramSample extends CachedHistogram {
-        private final List<Long> mSamples = new ArrayList<Long>();
-        private final TimeUnit mTimeUnit;
-
+    public static class TimesHistogramSample extends CachedMetrics.TimesHistogramSample {
         public TimesHistogramSample(String histogramName, TimeUnit timeUnit) {
-            super(histogramName);
-            mTimeUnit = timeUnit;
-        }
-
-        public void record(long sample) {
-            if (LibraryLoader.isInitialized()) {
-                recordWithNative(sample);
-            } else {
-                mSamples.add(sample);
-            }
-        }
-
-        private void recordWithNative(long sample) {
-            RecordHistogram.recordTimesHistogram(mHistogramName, sample, mTimeUnit);
-        }
-
-        @Override
-        protected void commitAndClear() {
-            for (Long sample : mSamples) {
-                recordWithNative(sample);
-            }
-            mSamples.clear();
+            super(histogramName, timeUnit);
         }
     }
 
@@ -222,7 +86,7 @@ public class LaunchMetrics {
         sTabUrls.clear();
 
         // Record generic cached events.
-        for (CachedHistogram event : CachedHistogram.sEvents) event.commitAndClear();
+        CachedMetrics.commitCachedMetrics();
     }
 
     /**

chrome/android/java/src/org/chromium/chrome/browser/metrics/MediaNotificationUma.java

@@ -4,7 +4,7 @@
 
 package org.chromium.chrome.browser.metrics;
 
-import static org.chromium.chrome.browser.metrics.LaunchMetrics.EnumeratedHistogramSample;
+import static org.chromium.base.metrics.CachedMetrics.EnumeratedHistogramSample;
 
 import android.content.Intent;
 
@@ -23,8 +23,7 @@ public class MediaNotificationUma {
             "org.chromium.chrome.browser.metrics.MediaNotificationUma.EXTRA_CLICK_SOURCE";
 
     private static final EnumeratedHistogramSample sClickSourceHistogram =
-            new LaunchMetrics.EnumeratedHistogramSample(
-                    "Media.Notification.Click", SOURCE_MAX);
+            new EnumeratedHistogramSample("Media.Notification.Click", SOURCE_MAX);
 
     /**
      * Record the UMA as specified by {@link intent}. The {@link intent} should contain intent extra

chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappAuthenticator.java

@@ -12,7 +12,7 @@ import android.os.SystemClock;
 import android.util.Log;
 
 import org.chromium.base.SecureRandomInitializer;
-import org.chromium.chrome.browser.metrics.LaunchMetrics.TimesHistogramSample;
+import org.chromium.base.metrics.CachedMetrics.TimesHistogramSample;
 
 import java.io.File;
 import java.io.FileInputStream;