[Android WebAPKs] Re-extract and optimize runtime library after Android OS upgrade

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

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkVersionManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkVersionManager.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkVersionManager.java
index 6fe56ec0bf39ece25fa10d6f8ae06de306c0ac4d..9cdf2c4c2fbd113ce31ae27a5d309482f8fad9a8 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkVersionManager.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebApkVersionManager.java
@@ -7,6 +7,7 @@ package org.chromium.chrome.browser.webapps;
 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.SharedPreferences;
+import android.os.Build;
 
 import org.chromium.base.CommandLine;
 import org.chromium.base.ContextUtils;
@@ -29,6 +30,13 @@ public class WebApkVersionManager {
     private static final String EXTRACTED_DEX_VERSION_PREF =
             "org.chromium.chrome.browser.webapps.extracted_dex_version";
 
+    /**
+     * Name of the shared preference for the Android OS version at the time that the dex was last
+     * extracted from Chrome's assets and optimized.
+     */
+    private static final String LAST_SDK_VERSION_PREF =
+            "org.chromium.chrome.browser.webapps.last_sdk_version";
+
     /**
      * Tries to extract the WebAPK runtime dex from the Chrome APK if it has not tried already.
      * Should not be called on UI thread.
@@ -38,19 +46,19 @@ public class WebApkVersionManager {
     public static void updateWebApksIfNeeded() {
         assert !ThreadUtils.runningOnUiThread();
 
-        // TODO(pkotwicz|hanxi): Detect whether the manifest of installed APKs needs to be updated.
-        // (crbug.com/604513)
-
         SharedPreferences preferences = ContextUtils.getAppSharedPreferences();
         int extractedDexVersion = preferences.getInt(EXTRACTED_DEX_VERSION_PREF, -1);
+        int lastSdkVersion = preferences.getInt(LAST_SDK_VERSION_PREF, -1);
         if (!CommandLine.getInstance().hasSwitch(
                     ChromeSwitches.ALWAYS_EXTRACT_WEBAPK_RUNTIME_DEX_ON_STARTUP)
-                && extractedDexVersion == WebApkVersion.CURRENT_RUNTIME_DEX_VERSION) {
+                && extractedDexVersion == WebApkVersion.CURRENT_RUNTIME_DEX_VERSION
+                && lastSdkVersion == Build.VERSION.SDK_INT) {
             return;
         }
 
         SharedPreferences.Editor editor = preferences.edit();
         editor.putInt(EXTRACTED_DEX_VERSION_PREF, WebApkVersion.CURRENT_RUNTIME_DEX_VERSION);
+        editor.putInt(LAST_SDK_VERSION_PREF, Build.VERSION.SDK_INT);
         editor.apply();
 
         Context context = ContextUtils.getApplicationContext();