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

Index: chrome/android/java/src/org/chromium/chrome/browser/webapps/ChromeWebApkHost.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/ChromeWebApkHost.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/ChromeWebApkHost.java
index b73fc416d8e6d1a06968dc2a2f29075eb7b6b524..89231d8a31780eacb26976a035c15271107d0bf3 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webapps/ChromeWebApkHost.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/ChromeWebApkHost.java
@@ -11,12 +11,16 @@ import android.os.StrictMode;
 import android.provider.Settings;
 import android.support.v7.app.AlertDialog;
 
+import org.chromium.base.Callback;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.Log;
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.chrome.R;
+import org.chromium.chrome.browser.ChromeApplication;
 import org.chromium.chrome.browser.ChromeFeatureList;
 import org.chromium.chrome.browser.ChromeVersionInfo;
+import org.chromium.chrome.browser.externalauth.ExternalAuthUtils;
+import org.chromium.chrome.browser.externalauth.UserRecoverableErrorHandler;
 import org.chromium.chrome.browser.preferences.ChromePreferenceManager;
 import org.chromium.webapk.lib.client.WebApkValidator;
 
@@ -26,6 +30,9 @@ import org.chromium.webapk.lib.client.WebApkValidator;
 public class ChromeWebApkHost {
     private static final String TAG = "ChromeWebApkHost";
 
+    /** Whether installing WebAPks from Google Play is possible. */
+    private static Boolean sCanUseGooglePlayInstall;
+
     private static Boolean sEnabledForTesting;
 
     public static void init() {
@@ -53,14 +60,74 @@ public class ChromeWebApkHost {
         return installingFromUnknownSourcesAllowed() || canUseGooglePlayToInstallWebApk();
     }
 
-    /** Return whether installing WebAPKs using Google Play is enabled. */
+    /**
+     * Initializes {@link sCanUseGooglePlayInstall}. It checks whether:
+     * 1) WebAPK is enabled;
+     * 2) Google Play Service is available on the device;
+     * 3) Google Play install is enabled by Chrome;
+     * 4) Google Play is up-to-date and with gServices flags turned on.
+     * It calls the Google Play Install API to update {@link sCanUseGooglePlayInstall}
+     * asynchronously.
+     */
+    public static void initCanUseGooglePlayToInstallWebApk() {
+        if (!isGooglePlayInstallEnabledByChromeFeature()

[pkotwicz, 2017/02/05 02:13:54]

I don't think that having a separate isGooglePlayInstallEnabledByChromeFeature()
function is necessary. You can just check !isEnabled() ||
!nativeCanUseGooglePlayToInstallWebApk() here

[Xi Han, 2017/02/06 18:03:43]

This function is also callded by ChromeApplicationInternal, which is in the
internal CL. I keep the |isGooglePlayInstallEnabledByChromeFeature|, but here
adopt your suggestions, since it is more clear to call them directly.

+                || !ExternalAuthUtils.getInstance().canUseGooglePlayServices(
+                        ContextUtils.getApplicationContext(),
+                        new UserRecoverableErrorHandler.Silent())) {
+            sCanUseGooglePlayInstall = false;
+            return;
+        }
+
+        ChromeApplication application = (ChromeApplication) ContextUtils.getApplicationContext();
+        GooglePlayWebApkInstallDelegate delegate = application.getGooglePlayWebApkInstallDelegate();
+        if (delegate == null) {
+            sCanUseGooglePlayInstall = false;
+            return;
+        }
+
+        Callback<Boolean> callback = new Callback<Boolean>() {
+            @Override
+            public void onResult(Boolean success) {
+                sCanUseGooglePlayInstall = success;
+            }
+        };
+        delegate.canUseInstallApi(callback);
+    }
+
+    /**
+     * Returns whether installing WebAPKs from Google Play is possible.
+     * If {@link sCanUseGooglePlayInstall} hasn't been set yet, it returns false immediately and
+     * calls the Google Play Install API to update {@link sCanUseGooglePlayInstall} asynchronously.
+     */
     public static boolean canUseGooglePlayToInstallWebApk() {
+        if (sCanUseGooglePlayInstall == null) {
+            sCanUseGooglePlayInstall = false;
+            initCanUseGooglePlayToInstallWebApk();
+        }
+        return sCanUseGooglePlayInstall;
+    }
+
+    /** Returns whether Google Play install is enabled by Chrome. */
+    public static boolean isGooglePlayInstallEnabledByChromeFeature() {
         return isEnabled() && nativeCanUseGooglePlayToInstallWebApk();

[dominickn, 2017/02/06 05:22:49]

I would move isEnabled() up to canInstallWebApk()

[Xi Han, 2017/02/06 18:03:43]

Removed. Also, I added additional call in WebApkInstallStatusReceiver (refer to
the internal CL).

     }
 
+    /**
+     * Returns whether installing WebAPKs is possible either from "unknown resources" or Google
+     * Play.
+     */
+    public static boolean canInstallWebApk() {
+        return canUseGooglePlayToInstallWebApk() || canInstallFromUnknownSources();
+    }
+
+    /** Returns whether installing WebAPKs from "unknown resources" is enabled. */
+    private static boolean canInstallFromUnknownSources() {
+        return isEnabled() && nativeCanInstallFromUnknownSources();

[dominickn, 2017/02/06 05:22:49]

I would move the isEnabled() check up to canInstallWebApk().

[Xi Han, 2017/02/06 18:03:43]

Remove |canInstallFromUnknownSources()|, since it is only called by
|canInstallWebApk()|.
. 

+    }
+
     @CalledByNative
-    private static boolean areWebApkEnabled() {
-        return ChromeWebApkHost.isEnabled();
+    private static boolean isWebApkInstallFlowAvailable() {

[dominickn, 2017/02/06 05:22:49]

Call this canInstallWebApk() to match the native side? Plus, you should just be
able to inline isEnabled() || canUseGooglePlayToInstallWebApk() ||
canInstallFromUnknownSources() in here.

[Xi Han, 2017/02/06 18:03:43]

Done.

+        return ChromeWebApkHost.canInstallWebApk();
     }
 
     /**
@@ -155,4 +222,5 @@ public class ChromeWebApkHost {
     }
 
     private static native boolean nativeCanUseGooglePlayToInstallWebApk();
+    private static native boolean nativeCanInstallFromUnknownSources();
 }