Improves how cornercase scenarios are handled:

- Bug reports without screenshots are supported.
- Shows a toast message when the bugreport file cannot be read.

BUG: 25751868
Change-Id: I4ed2c47a89b373cf878720ebcba90c96bd51342b
diff --git a/packages/Shell/res/values/strings.xml b/packages/Shell/res/values/strings.xml
index 3db0848..4469d38 100644
--- a/packages/Shell/res/values/strings.xml
+++ b/packages/Shell/res/values/strings.xml
@@ -33,4 +33,8 @@
 
     <!-- Title for documents backend that offers bugreports. -->
     <string name="bugreport_storage_title">Bug reports</string>
+
+    <!-- Toast message sent when the bugreport file could be read. -->
+    <string name="bugreport_unreadable_text">Bug report file could not be read</string>
+
 </resources>
diff --git a/packages/Shell/src/com/android/shell/BugreportReceiver.java b/packages/Shell/src/com/android/shell/BugreportReceiver.java
index e90a3b5..c264372 100644
--- a/packages/Shell/src/com/android/shell/BugreportReceiver.java
+++ b/packages/Shell/src/com/android/shell/BugreportReceiver.java
@@ -37,6 +37,7 @@
 import android.text.format.DateUtils;
 import android.util.Log;
 import android.util.Patterns;
+import android.widget.Toast;
 
 import com.google.android.collect.Lists;
 import libcore.io.Streams;
@@ -105,6 +106,13 @@
      */
     private void triggerLocalNotification(final Context context, final File bugreportFile,
             final File screenshotFile) {
+        if (!bugreportFile.exists() || !bugreportFile.canRead()) {
+            Log.e(TAG, "Could not read bugreport file " + bugreportFile);
+            Toast.makeText(context, context.getString(R.string.bugreport_unreadable_text),
+                    Toast.LENGTH_LONG).show();
+            return;
+        }
+
         boolean isPlainText = bugreportFile.getName().toLowerCase().endsWith(".txt");
         if (!isPlainText) {
             // Already zipped, send it right away.
@@ -141,10 +149,12 @@
         intent.putExtra(Intent.EXTRA_TEXT, messageBody);
         final ClipData clipData = new ClipData(null, new String[] { mimeType },
                 new ClipData.Item(null, null, null, bugreportUri));
-        clipData.addItem(new ClipData.Item(null, null, null, screenshotUri));
+        final ArrayList<Uri> attachments = Lists.newArrayList(bugreportUri);
+        if (screenshotUri != null) {
+            clipData.addItem(new ClipData.Item(null, null, null, screenshotUri));
+            attachments.add(screenshotUri);
+        }
         intent.setClipData(clipData);
-
-        final ArrayList<Uri> attachments = Lists.newArrayList(bugreportUri, screenshotUri);
         intent.putParcelableArrayListExtra(Intent.EXTRA_STREAM, attachments);
 
         final Account sendToAccount = findSendToAccount(context);
@@ -162,8 +172,8 @@
             File screenshotFile) {
         // Files are kept on private storage, so turn into Uris that we can
         // grant temporary permissions for.
-        final Uri bugreportUri = FileProvider.getUriForFile(context, AUTHORITY, bugreportFile);
-        final Uri screenshotUri = FileProvider.getUriForFile(context, AUTHORITY, screenshotFile);
+        final Uri bugreportUri = getUri(context, bugreportFile);
+        final Uri screenshotUri = getUri(context, screenshotFile);
 
         Intent sendIntent = buildSendIntent(context, bugreportUri, screenshotUri);
         Intent notifIntent;
@@ -272,6 +282,10 @@
         return foundAccount;
     }
 
+    private static Uri getUri(Context context, File file) {
+        return file != null ? FileProvider.getUriForFile(context, AUTHORITY, file) : null;
+    }
+
     private static File getFileExtra(Intent intent, String key) {
         final String path = intent.getStringExtra(key);
         if (path != null) {