Android: Add work-around for renderers not being able to access odex

This causes trichrome's dex to be compile with "speed" rather than
"speed-profile", which is a substantial binary size regression.

Also adds a histogram to track when the work-around happens.

Bug: 1152970, 1159608
Change-Id: I25e2c350b54724613234b23505078f5df88d9cf4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2602657
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Reviewed-by: Clark DuVall <cduvall@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840328}

base/BUILD.gn

@@ -3989,6 +3989,13 @@ if (is_android) {
       "test/android/junit/src/org/chromium/base/test/BaseRobolectricTestRunner.java",
       "test/android/junit/src/org/chromium/base/test/util/TestRunnerTestRule.java",
     ]
+
+    # Make sure robolectric tests have classes filtered out of base_java by
+    # jar_excluded_patterns.
+    srcjar_deps = [
+      ":base_build_config_gen",
+      ":base_native_libraries_gen",
+    ]
     deps = [
       ":base_java",
       "//testing/android/junit:junit_test_support",

chrome/android/BUILD.gn

@@ -2152,6 +2152,8 @@ android_library("base_module_java") {
     "java/src/org/chromium/chrome/browser/ChromeBackgroundService.java",
     "java/src/org/chromium/chrome/browser/ChromeBackupAgent.java",
     "java/src/org/chromium/chrome/browser/DeferredStartupHandler.java",
+    "java/src/org/chromium/chrome/browser/base/DexFixer.java",
+    "java/src/org/chromium/chrome/browser/base/DexFixerReason.java",
     "java/src/org/chromium/chrome/browser/base/SplitChromeApplication.java",
     "java/src/org/chromium/chrome/browser/base/SplitCompatAppComponentFactory.java",
     "java/src/org/chromium/chrome/browser/base/SplitCompatApplication.java",

chrome/android/chrome_junit_test_java_sources.gni

@@ -16,6 +16,7 @@ chrome_junit_test_java_sources = [
   "junit/src/org/chromium/chrome/browser/background_sync/BackgroundSyncGooglePlayServicesCheckerTest.java",
   "junit/src/org/chromium/chrome/browser/background_sync/PeriodicBackgroundSyncChromeWakeUpTaskTest.java",
   "junit/src/org/chromium/chrome/browser/background_task_scheduler/NativeBackgroundTaskTest.java",
+  "junit/src/org/chromium/chrome/browser/base/DexFixerTest.java",
   "junit/src/org/chromium/chrome/browser/base/SplitPreloaderTest.java",
   "junit/src/org/chromium/chrome/browser/bookmarks/ReadingListSectionHeaderTest.java",
   "junit/src/org/chromium/chrome/browser/browserservices/ClearDataDialogResultRecorderTest.java",

chrome/android/java/src/org/chromium/chrome/browser/base/DexFixer.java

+// Copyright 2020 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.chrome.browser.base;
+
+import android.content.pm.ApplicationInfo;
+import android.os.Build;
+import android.system.ErrnoException;
+import android.system.Os;
+import android.system.StructStat;
+
+import androidx.annotation.RequiresApi;
+import androidx.annotation.VisibleForTesting;
+import androidx.annotation.WorkerThread;
+
+import dalvik.system.DexFile;
+
+import org.chromium.base.BuildConfig;
+import org.chromium.base.BuildInfo;
+import org.chromium.base.ContextUtils;
+import org.chromium.base.Log;
+import org.chromium.base.compat.ApiHelperForM;
+import org.chromium.base.compat.ApiHelperForO;
+import org.chromium.base.library_loader.NativeLibraries;
+import org.chromium.base.metrics.RecordHistogram;
+import org.chromium.base.task.PostTask;
+import org.chromium.base.task.TaskTraits;
+import org.chromium.chrome.browser.DeferredStartupHandler;
+import org.chromium.chrome.browser.preferences.ChromePreferenceKeys;
+import org.chromium.chrome.browser.preferences.SharedPreferencesManager;
+import org.chromium.chrome.browser.version.ChromeVersionInfo;
+
+import java.io.File;
+import java.io.IOException;
+
+@RequiresApi(Build.VERSION_CODES.O)
+class DexFixer {
+    private static final String TAG = "DexFixer";
+    private static boolean sHasIsolatedSplits;
+
+    static void setHasIsolatedSplits(boolean value) {
+        sHasIsolatedSplits = value;
+    }
+
+    static void scheduleDexFix() {
+        ApplicationInfo appInfo = ContextUtils.getApplicationContext().getApplicationInfo();
+        // All bugs are fixed after Q.
+        if (Build.VERSION.SDK_INT > Build.VERSION_CODES.Q) {
+            return;
+        }
+        // Fixes are never required for system image installs, since we can trust those to be valid
+        // and world-readable.
+        if ((appInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0) {
+            return;
+        }
+        // Skip the workaround on local builds to avoid affecting perf bots.
+        // https://bugs.chromium.org/p/chromium/issues/detail?id=1160070
+        if (ChromeVersionInfo.isLocalBuild() && ChromeVersionInfo.isOfficialBuild()) {
+            return;
+        }
+
+        // Wait until startup completes so this doesn't slow down early startup or mess with
+        // compiled dex files before they get loaded initially.
+        DeferredStartupHandler.getInstance().addDeferredTask(() -> {
+            // BEST_EFFORT will only affect when the task runs, the dexopt will run with
+            // normal priority (but in a separate process, due to using Runtime.exec()).
+            PostTask.postTask(TaskTraits.BEST_EFFORT_MAY_BLOCK,
+                    () -> { fixDexIfNecessary(Runtime.getRuntime()); });
+        });
+    }
+
+    @WorkerThread
+    @VisibleForTesting
+    static void fixDexIfNecessary(Runtime runtime) {
+        ApplicationInfo appInfo = ContextUtils.getApplicationContext().getApplicationInfo();
+        @DexFixerReason
+        int reason = needsDexCompile(appInfo);
+        if (reason > DexFixerReason.NOT_NEEDED) {
+            Log.w(TAG, "Triggering dex compile. Reason=%d", reason);
+            try {
+                String cmd = "cmd package compile -r shared ";
+                if (reason == DexFixerReason.NOT_READABLE && BuildConfig.ISOLATED_SPLITS_ENABLED) {
+                    // Isolated processes need only access the base split.
+                    String apkBaseName = new File(appInfo.sourceDir).getName();
+                    cmd += String.format("--split %s ", apkBaseName);
+                }
+                cmd += ContextUtils.getApplicationContext().getPackageName();
+                runtime.exec(cmd);
+            } catch (IOException e) {
+                reason = DexFixerReason.FAILED_TO_RUN;
+            }
+        }
+        RecordHistogram.recordEnumeratedHistogram("Android.DexFixer", reason, DexFixerReason.COUNT);
+    }
+
+    private static String odexPathFromApkPath(String apkPath) {
+        // Based on https://cs.android.com/search?q=OatFileAssistant::DexLocationToOdexNames
+        boolean is64Bit = ApiHelperForM.isProcess64Bit();
+        String isaName;
+        if (NativeLibraries.sCpuFamily == NativeLibraries.CPU_FAMILY_ARM) {
+            isaName = is64Bit ? "arm64" : "arm";
+        } else {
+            isaName = is64Bit ? "x86_64" : "x86";
+        }
+        // E.g. /data/app/org.chromium.chrome-qtmmjyN79ucfPKm0ZVZMHg==/base.apk
+        File apkFile = new File(apkPath);
+        String baseName = apkFile.getName();
+        baseName = baseName.substring(0, baseName.lastIndexOf('.'));
+        return String.format("%s/oat/%s/%s.odex", apkFile.getParent(), isaName, baseName);
+    }
+
+    private static @DexFixerReason int needsDexCompile(ApplicationInfo appInfo) {
+        // Android O MR1 has a bug where bg-dexopt-job will break optimized dex files for isolated
+        // splits. This leads to *very* slow startup on those devices. To mitigate this, we attempt
+        // to force a dex compile if necessary.
+        if (sHasIsolatedSplits && Build.VERSION.SDK_INT == Build.VERSION_CODES.O_MR1) {
+            // If the app has just been updated, it will be compiled with quicken. The next time
+            // bg-dexopt-job runs it will break the optimized dex for splits. If we force compile
+            // now, then bg-dexopt-job won't mess up the splits, and we save the user a slow
+            // startup.
+            SharedPreferencesManager prefManager = SharedPreferencesManager.getInstance();
+            long versionCode = BuildInfo.getInstance().versionCode;
+            if (prefManager.readLong(ChromePreferenceKeys.ISOLATED_SPLITS_DEX_COMPILE_VERSION)
+                    != versionCode) {
+                // Compiling the dex is an asynchronous operation anyways, so update the pref here
+                // rather than attempting to wait.
+                prefManager.writeLong(
+                        ChromePreferenceKeys.ISOLATED_SPLITS_DEX_COMPILE_VERSION, versionCode);
+                return DexFixerReason.O_MR1_AFTER_UPDATE;
+            }
+
+            // Check for corrupt dex.
+            String[] splitNames = ApiHelperForO.getSplitNames(appInfo);
+            if (splitNames != null) {
+                for (int i = 0; i < splitNames.length; i++) {
+                    // Ignore config splits like "config.en".
+                    if (splitNames[i].contains(".")) {
+                        continue;
+                    }
+                    try {
+                        if (DexFile.isDexOptNeeded(appInfo.splitSourceDirs[i])) {
+                            return DexFixerReason.O_MR1_CORRUPTED;
+                        }
+                    } catch (IOException e) {
+                        return DexFixerReason.O_MR1_IO_EXCEPTION;
+                    }
+                }
+            }
+        }
+
+        String oatPath = odexPathFromApkPath(appInfo.sourceDir);
+        try {
+            StructStat st = Os.stat(oatPath);
+            if ((st.st_mode & 0007) == 0) {
+                return DexFixerReason.NOT_READABLE;
+            }
+        } catch (ErrnoException e) {
+            return DexFixerReason.STAT_FAILED;
+        }
+        return DexFixerReason.NOT_NEEDED;
+    }
+}

chrome/android/java/src/org/chromium/chrome/browser/base/DexFixerReason.java

+// Copyright 2020 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.chrome.browser.base;
+
+import androidx.annotation.IntDef;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+/** Histogram enum to monitor DexFixer. */
+@IntDef({DexFixerReason.STAT_FAILED, DexFixerReason.FAILED_TO_RUN, DexFixerReason.NOT_NEEDED,
+        DexFixerReason.O_MR1_AFTER_UPDATE, DexFixerReason.O_MR1_CORRUPTED,
+        DexFixerReason.O_MR1_IO_EXCEPTION, DexFixerReason.NOT_READABLE})
+@Retention(RetentionPolicy.SOURCE)
+public @interface DexFixerReason {
+    // These values are persisted to logs. Entries should not be renumbered and
+    // numeric values should never be reused.
+    int STAT_FAILED = 0;
+    int FAILED_TO_RUN = 1;
+    int NOT_NEEDED = 2;
+    // Values greater than NOT_NEEDED trigger Dexopt.
+    int O_MR1_AFTER_UPDATE = 5;
+    int O_MR1_CORRUPTED = 6;
+    int O_MR1_IO_EXCEPTION = 7;
+    int NOT_READABLE = 8;
+    int COUNT = 9;
+}

chrome/android/java/src/org/chromium/chrome/browser/base/SplitChromeApplication.java

@@ -14,22 +14,11 @@ import android.content.pm.PackageManager;
 import android.os.Build;
 import android.os.SystemClock;
 
-import dalvik.system.DexFile;
-
 import org.chromium.base.ActivityState;
 import org.chromium.base.ApplicationStatus;
 import org.chromium.base.JNIUtils;
-import org.chromium.base.Log;
-import org.chromium.base.PackageUtils;
 import org.chromium.base.TraceEvent;
-import org.chromium.base.compat.ApiHelperForO;
 import org.chromium.base.metrics.RecordHistogram;
-import org.chromium.base.task.PostTask;
-import org.chromium.base.task.TaskTraits;
-import org.chromium.chrome.browser.DeferredStartupHandler;
-import org.chromium.chrome.browser.preferences.ChromePreferenceKeys;
-import org.chromium.chrome.browser.preferences.SharedPreferencesManager;
-import org.chromium.chrome.browser.version.ChromeVersionInfo;
 
 import java.lang.reflect.Field;
 
@@ -68,13 +57,15 @@ public class SplitChromeApplication extends SplitCompatApplication {
     protected void attachBaseContext(Context context) {
         super.attachBaseContext(context);
         if (isBrowserProcess()) {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+                DexFixer.setHasIsolatedSplits(true);
+            }
             setImplSupplier(() -> {
                 Context chromeContext = SplitCompatUtils.createChromeContext(this);
                 return (Impl) SplitCompatUtils.newInstance(
                         chromeContext, mChromeApplicationClassName);
             });
             applyActivityClassLoaderWorkaround();
-            applyDexCompileWorkaround();
         } else {
             setImplSupplier(() -> createNonBrowserApplication());
         }
@@ -158,71 +149,6 @@ public class SplitChromeApplication extends SplitCompatApplication {
                 });
     }
 
-    /**
-     * Android OMR1 has a bug where bg-dexopt-job will break optimized dex files for splits. This
-     * leads to *very* slow startup on those devices. To mitigate this, we attempt to force a dex
-     * compile if necessary.
-     */
-    private void applyDexCompileWorkaround() {
-        // This bug only happens in OMR1. Skip the workaround on local builds to avoid affecting
-        // perf bots.
-        if (Build.VERSION.SDK_INT != Build.VERSION_CODES.O_MR1
-                || ChromeVersionInfo.isLocalBuild()) {
-            return;
-        }
-        // Wait until startup completes so this doesn't slow down early startup or mess with
-        // compiled dex files before they get loaded initially.
-        DeferredStartupHandler.getInstance().addDeferredTask(() -> {
-            // BEST_EFFORT will only affect when the task runs, the dexopt will run with
-            // normal priority (but in a separate process, due to using Runtime.exec()).
-            PostTask.postTask(TaskTraits.BEST_EFFORT_MAY_BLOCK, () -> {
-                try {
-                    // If the app has just been updated, it will be compiled with
-                    // quicken. The next time bg-dexopt-job runs it will break the
-                    // optimized dex for splits. If we force compile now, then
-                    // bg-dexopt-job won't mess up the splits, and we save the user a
-                    // slow startup.
-                    if (needsDexCompileAfterUpdate()) {
-                        performDexCompile();
-                        return;
-                    }
-
-                    // Make sure all splits are compiled correclty, and if not force a
-                    // compile.
-                    String[] splitNames = ApiHelperForO.getSplitNames(getApplicationInfo());
-                    for (int i = 0; i < splitNames.length; i++) {
-                        // Ignore config splits like "config.en".
-                        if (splitNames[i].contains(".")) {
-                            continue;
-                        }
-                        if (DexFile.isDexOptNeeded(getApplicationInfo().splitSourceDirs[i])) {
-                            performDexCompile();
-                            return;
-                        }
-                    }
-                } catch (Exception e) {
-                    Log.e(TAG, "Error compiling dex.", e);
-                }
-            });
-        });
-    }
-
-    /** Returns whether the dex has been compiled since the last app update. */
-    private boolean needsDexCompileAfterUpdate() {
-        return SharedPreferencesManager.getInstance().readInt(
-                       ChromePreferenceKeys.ISOLATED_SPLITS_DEX_COMPILE_VERSION)
-                != PackageUtils.getPackageVersion(this, getPackageName());
-    }
-
-    /** Compiles dex for the app, and sets the pref key tracking the latest compiled version. */
-    private void performDexCompile() throws Exception {
-        Runtime.getRuntime().exec(
-                new String[] {"cmd", "package", "compile", "-r", "shared", getPackageName()});
-        SharedPreferencesManager.getInstance().writeInt(
-                ChromePreferenceKeys.ISOLATED_SPLITS_DEX_COMPILE_VERSION,
-                PackageUtils.getPackageVersion(this, getPackageName()));
-    }
-
     private static void replaceClassLoader(Context baseContext, ClassLoader classLoader) {
         while (baseContext instanceof ContextWrapper) {
             baseContext = ((ContextWrapper) baseContext).getBaseContext();

chrome/android/java/src/org/chromium/chrome/browser/base/SplitCompatApplication.java

@@ -9,6 +9,7 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.pm.ApplicationInfo;
 import android.content.res.Configuration;
+import android.os.Build;
 import android.os.Bundle;
 
 import androidx.annotation.CallSuper;
@@ -145,6 +146,10 @@ public class SplitCompatApplication extends Application {
 
         if (isBrowserProcess) {
             checkAppBeingReplaced();
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+                // Fixes are never required before O (where "cmd package compile" does not exist).
+                DexFixer.scheduleDexFix();
+            }
 
             PathUtils.setPrivateDataDirectorySuffix(PRIVATE_DATA_DIRECTORY_SUFFIX);
             // Renderer and GPU processes have command line passed to them via IPC

chrome/android/junit/src/org/chromium/chrome/browser/base/DexFixerTest.java

+// Copyright 2020 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.chrome.browser.base;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+
+import android.content.pm.ApplicationInfo;
+import android.os.Build;
+import android.system.Os;
+import android.system.StructStat;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.Mockito;
+import org.mockito.junit.MockitoJUnit;
+import org.mockito.junit.MockitoRule;
+import org.mockito.quality.Strictness;
+import org.robolectric.annotation.Config;
+import org.robolectric.annotation.Implementation;
+import org.robolectric.annotation.Implements;
+import org.robolectric.shadow.api.Shadow;
+import org.robolectric.shadows.ShadowDexFile;
+import org.robolectric.util.ReflectionHelpers.ClassParameter;
+
+import org.chromium.base.BuildInfo;
+import org.chromium.base.ContextUtils;
+import org.chromium.base.metrics.test.ShadowRecordHistogram;
+import org.chromium.base.test.BaseRobolectricTestRunner;
+import org.chromium.chrome.browser.preferences.ChromePreferenceKeys;
+import org.chromium.chrome.browser.preferences.SharedPreferencesManager;
+
+import java.io.IOException;
+
+/**
+ * Unit tests for {@link DexFixer}.
+ */
+@RunWith(BaseRobolectricTestRunner.class)
+@Config(manifest = Config.NONE, sdk = Build.VERSION_CODES.O_MR1,
+        shadows = {ShadowRecordHistogram.class, DexFixerTest.ShadowOs.class})
+public class DexFixerTest {
+    @Implements(Os.class)
+    public static class ShadowOs {
+        static boolean sWorldReadable = true;
+        @Implementation
+        public static StructStat stat(String path) {
+            if (path.endsWith(".odex")) {
+                return new StructStat(
+                        0, 0, sWorldReadable ? 0777 : 0700, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
+            }
+            return Shadow.directlyOn(Os.class, "stat", ClassParameter.from(String.class, path));
+        }
+    }
+
+    @Mock
+    private Runtime mMockRuntime;
+    @Rule
+    public MockitoRule mMockitoRule = MockitoJUnit.rule().strictness(Strictness.STRICT_STUBS);
+
+    @Before
+    public void setUp() {
+        ShadowOs.sWorldReadable = true;
+    }
+
+    @After
+    public void tearDown() {
+        ShadowRecordHistogram.reset();
+        DexFixer.setHasIsolatedSplits(false);
+    }
+
+    private static int getReason() {
+        int ret = -1;
+        for (int i = 0; i < DexFixerReason.COUNT; ++i) {
+            int count =
+                    ShadowRecordHistogram.getHistogramValueCountForTesting("Android.DexFixer", i);
+            if (count > 0) {
+                assertThat(count).isEqualTo(1);
+                assertThat(ret).isEqualTo(-1);
+                ret = i;
+            }
+        }
+        assertThat(ret).isNotEqualTo(-1);
+        return ret;
+    }
+
+    private void verifyDexOpt() {
+        try {
+            verify(mMockRuntime).exec(Mockito.matches("cmd package compile -r shared \\S+"));
+        } catch (IOException e) {
+            // Mocks don't actually throw...
+        }
+    }
+
+    @Test
+    public void testFixDexIfNecessary_notNeeded() {
+        DexFixer.fixDexIfNecessary(mMockRuntime);
+        assertThat(getReason()).isEqualTo(DexFixerReason.NOT_NEEDED);
+        verifyNoMoreInteractions(mMockRuntime);
+    }
+
+    @Test
+    public void testFixDexIfNecessary_notReadable() {
+        ShadowOs.sWorldReadable = false;
+        DexFixer.fixDexIfNecessary(mMockRuntime);
+        assertThat(getReason()).isEqualTo(DexFixerReason.NOT_READABLE);
+        verifyDexOpt();
+    }
+
+    @Test
+    public void testFixDexIfNecessary_update() {
+        DexFixer.setHasIsolatedSplits(true);
+        DexFixer.fixDexIfNecessary(mMockRuntime);
+        assertThat(getReason()).isEqualTo(DexFixerReason.O_MR1_AFTER_UPDATE);
+        verifyDexOpt();
+
+        // Second time should be okay.
+        ShadowRecordHistogram.reset();
+        DexFixer.fixDexIfNecessary(mMockRuntime);
+        assertThat(getReason()).isEqualTo(DexFixerReason.NOT_NEEDED);
+        verifyNoMoreInteractions(mMockRuntime);
+    }
+
+    @Test
+    public void testFixDexIfNecessary_corruptDex() {
+        ApplicationInfo appInfo = ContextUtils.getApplicationContext().getApplicationInfo();
+        appInfo.splitNames = new String[] {"a"};
+        appInfo.splitSourceDirs = new String[] {"/a.apk"};
+        DexFixer.setHasIsolatedSplits(true);
+        SharedPreferencesManager.getInstance().writeLong(
+                ChromePreferenceKeys.ISOLATED_SPLITS_DEX_COMPILE_VERSION,
+                BuildInfo.getInstance().versionCode);
+
+        ShadowDexFile.setIsDexOptNeeded(true);
+        DexFixer.fixDexIfNecessary(mMockRuntime);
+        assertThat(getReason()).isEqualTo(DexFixerReason.O_MR1_CORRUPTED);
+        verifyDexOpt();
+    }
+
+    @Test
+    public void testFixDexIfNecessary_notReadableWithSplits() {
+        ApplicationInfo appInfo = ContextUtils.getApplicationContext().getApplicationInfo();
+        appInfo.splitNames = new String[] {"ignored.en"};
+        DexFixer.setHasIsolatedSplits(true);
+        ShadowOs.sWorldReadable = false;
+        SharedPreferencesManager.getInstance().writeLong(
+                ChromePreferenceKeys.ISOLATED_SPLITS_DEX_COMPILE_VERSION,
+                BuildInfo.getInstance().versionCode);
+
+        DexFixer.fixDexIfNecessary(mMockRuntime);
+        assertThat(getReason()).isEqualTo(DexFixerReason.NOT_READABLE);
+        verifyDexOpt();
+    }
+}

tools/metrics/histograms/enums.xml

@@ -17349,6 +17349,16 @@ metrics consent we also won't be able to send UMA metrics. -->
   <int value="7" label="Elements - Accessibility"/>
 </enum>
 
+<enum name="DexFixerReason">
+  <int value="0" label="Os.stat() failed"/>
+  <int value="1" label="Runtime.exec() failed"/>
+  <int value="2" label="Dexopt not needed"/>
+  <int value="5" label="Preemptive Dexopt after app updated"/>
+  <int value="6" label="DexFile.isDexOptNeeded() returned true"/>
+  <int value="7" label="DexFile.isDexOptNeeded() threw"/>
+  <int value="8" label="Dex files not world-readable"/>
+</enum>
+
 <enum name="DiagnosticsRecoveryRun">
   <int value="0" label="Recovery not run"/>
   <int value="1" label="Recovery run because of crash"/>

tools/metrics/histograms/histograms_xml/android/histograms.xml

@@ -607,6 +607,16 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
+<histogram name="Android.DexFixer" enum="DexFixerReason"
+    expires_after="2021-12-01">
+  <owner>agrieve@chromium.org</owner>
+  <owner>cduvall@chromium.org</owner>
+  <summary>
+    Records the number of times Chrome runs &quot;cmd package compile&quot; to
+    fix dexopt issues, and for what reason.
+  </summary>
+</histogram>
+
 <histogram name="Android.DirectAction.Perform" enum="DirectActionId"
     expires_after="M90">
   <owner>szermatt@chromium.org</owner>