Make sure we cannot use packages targeting pre-O as WebView packages.

Using a WebView package targeting a release before O as WebView provider
on O will cause crashes (because of incompatibility issues), this CL
makes us interpret a package targeting a pre-O release as being invalid
on O.

Also remove the code that lets us fall back to loading the old
WebViewChromiumFactoryProvider (pre-O) class.

Bug: 34773740
Bug: 34180497
Test: Ensure WebView provider with targetSdkVersion="O" shows up in the
WebView Implementation Dev Setting, ensure targetSdkVersion=25 doesn't
show up.
Test: Add WVUS unit test to ensure a packages with targetSdkVersion < 26
are considered invalid, and > 26 are valid. Run WVUS unit tests.

Change-Id: I4d80d46019e2522bc3fc6068712d28eedb31fcce

core/java/android/webkit/UserPackage.java

@@ -20,6 +20,7 @@ import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager.NameNotFoundException;
 import android.content.pm.UserInfo;
+import android.os.Build;
 import android.os.UserManager;
 
 import java.util.ArrayList;
@@ -77,6 +78,15 @@ public class UserPackage {
                         & ApplicationInfo.PRIVATE_FLAG_HIDDEN) == 0));
     }
 
+    /**
+     * Returns whether the package represented by {@param packageInfo} targets a sdk version
+     * supported by the current framework version.
+     */
+    public static boolean hasCorrectTargetSdkVersion(PackageInfo packageInfo) {
+        // TODO(gsennton) use Build.VERSION_CODES.O when that has been updated.
+        return packageInfo.applicationInfo.targetSdkVersion > Build.VERSION_CODES.N_MR1;
+    }
+
     public UserInfo getUserInfo() {
         return mUserInfo;
     }

core/java/android/webkit/WebViewFactory.java

@@ -145,18 +145,10 @@ public final class WebViewFactory {
     /**
      * @hide
      */
-    public static Class<WebViewFactoryProvider> getWebViewProviderClass(  ClassLoader clazzLoader)
-            throws ClassNotFoundException{
-        try {
-            return (Class<WebViewFactoryProvider>) Class.forName(CHROMIUM_WEBVIEW_FACTORY,
-                    true, clazzLoader);
-        } catch (ClassNotFoundException e) {
-            // TODO: This loads the provider which is not built for O, should be removed
-            // before the release.
-            return (Class<WebViewFactoryProvider>) Class.forName(
-                    "com.android.webview.chromium.WebViewChromiumFactoryProvider",
-                    true, clazzLoader);
-        }
+    public static Class<WebViewFactoryProvider> getWebViewProviderClass(ClassLoader clazzLoader)
+            throws ClassNotFoundException {
+        return (Class<WebViewFactoryProvider>) Class.forName(CHROMIUM_WEBVIEW_FACTORY,
+                true, clazzLoader);
     }
 
     /**
@@ -225,15 +217,10 @@ public final class WebViewFactory {
                     }
                 }
 
-                Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "providerClass.newInstance()");
+                Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactoryProvider invocation");
                 try {
-                    if (staticFactory != null) {
-                        sProviderInstance = (WebViewFactoryProvider)
-                                staticFactory.invoke(null, new WebViewDelegate());
-                    } else {
-                        sProviderInstance = providerClass.getConstructor(WebViewDelegate.class)
-                                .newInstance(new WebViewDelegate());
-                    }
+                    sProviderInstance = (WebViewFactoryProvider)
+                            staticFactory.invoke(null, new WebViewDelegate());
                     if (DEBUG) Log.v(LOGTAG, "Loaded provider: " + sProviderInstance);
                     return sProviderInstance;
                 } catch (Exception e) {
@@ -384,8 +371,7 @@ public final class WebViewFactory {
                 Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "Class.forName()");
                 try {
                     return getWebViewProviderClass(clazzLoader);
-                }
-                finally {
+                } finally {
                     Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
                 }
             } catch (ClassNotFoundException e) {

services/core/java/com/android/server/webkit/WebViewUpdateServiceImpl.java

@@ -630,6 +630,10 @@ public class WebViewUpdateServiceImpl {
          */
         public boolean isValidProvider(WebViewProviderInfo configInfo,
                 PackageInfo packageInfo) {
+            // Ensure the provider targets this framework release (or a later one).
+            if (!UserPackage.hasCorrectTargetSdkVersion(packageInfo)) {
+                return false;
+            }
             if (!versionCodeGE(packageInfo.versionCode, getMinimumVersionCode())
                     && !mSystemInterface.systemIsDebuggable()) {
                 // Webview providers may be downgraded arbitrarily low, prevent that by enforcing

services/tests/servicestests/src/com/android/server/webkit/WebViewUpdateServiceTest.java

@@ -16,6 +16,7 @@
 
 package com.android.server.webkit;
 
+import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
@@ -24,6 +25,7 @@ import android.content.Context;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageInfo;
 import android.content.pm.Signature;
+import android.os.Build;
 import android.os.Bundle;
 import android.support.test.InstrumentationRegistry;
 import android.support.test.runner.AndroidJUnit4;
@@ -174,6 +176,8 @@ public class WebViewUpdateServiceTest {
             // no flag means invalid
             p.applicationInfo.metaData.putString(WEBVIEW_LIBRARY_FLAG, "blah");
         }
+        // Default to this package being valid in terms of targetSdkVersion.
+        p.applicationInfo.targetSdkVersion = Build.VERSION_CODES.CUR_DEVELOPMENT;
         return p;
     }
 
@@ -1614,4 +1618,42 @@ public class WebViewUpdateServiceTest {
         checkPreparationPhasesForPackage(primaryPackage, 3);
         assertTrue(mWebViewUpdateServiceImpl.isMultiProcessEnabled());
     }
+
+    /**
+     * Ensure that packages with a targetSdkVersion targeting the current platform are valid, and
+     * that packages targeting an older version are not valid.
+     */
+    @Test
+    public void testTargetSdkVersionValidity() {
+        PackageInfo newSdkPackage = createPackageInfo("newTargetSdkPackage",
+            true /* enabled */, true /* valid */, true /* installed */);
+        newSdkPackage.applicationInfo.targetSdkVersion = Build.VERSION_CODES.CUR_DEVELOPMENT;
+        PackageInfo currentSdkPackage = createPackageInfo("currentTargetSdkPackage",
+            true /* enabled */, true /* valid */, true /* installed */);
+        currentSdkPackage.applicationInfo.targetSdkVersion = Build.VERSION_CODES.N_MR1+1;
+        PackageInfo oldSdkPackage = createPackageInfo("oldTargetSdkPackage",
+            true /* enabled */, true /* valid */, true /* installed */);
+        oldSdkPackage.applicationInfo.targetSdkVersion = Build.VERSION_CODES.N_MR1;
+
+        WebViewProviderInfo newSdkProviderInfo =
+                new WebViewProviderInfo(newSdkPackage.packageName, "", true, false, null);
+        WebViewProviderInfo currentSdkProviderInfo =
+                new WebViewProviderInfo(currentSdkPackage.packageName, "", true, false, null);
+        WebViewProviderInfo[] packages = new WebViewProviderInfo[] {
+            new WebViewProviderInfo(oldSdkPackage.packageName, "", true, false, null),
+            currentSdkProviderInfo, newSdkProviderInfo};
+        setupWithPackages(packages, true);
+;
+        mTestSystemImpl.setPackageInfo(newSdkPackage);
+        mTestSystemImpl.setPackageInfo(currentSdkPackage);
+        mTestSystemImpl.setPackageInfo(oldSdkPackage);
+
+        assertArrayEquals(new WebViewProviderInfo[]{currentSdkProviderInfo, newSdkProviderInfo},
+                mWebViewUpdateServiceImpl.getValidWebViewPackages());
+
+        runWebViewBootPreparationOnMainSync();
+
+        checkPreparationPhasesForPackage(currentSdkPackage.packageName,
+                1 /* first preparation phase */);
+    }
 }