Utilities.trim never returns null.

This fixes a crash loop I was seeing on my device and also
preemptively fixes similar NullPointerExceptions.

Bug: 213931730
Test: Manually verified crash loop stopped with this change.
Change-Id: I8d2fc8475d42ac60b7fdc9219421a8c9733c7b9f
diff --git a/src/com/android/launcher3/BubbleTextView.java b/src/com/android/launcher3/BubbleTextView.java
index 5d41741..041bee9 100644
--- a/src/com/android/launcher3/BubbleTextView.java
+++ b/src/com/android/launcher3/BubbleTextView.java
@@ -37,6 +37,7 @@
 import android.graphics.drawable.Drawable;
 import android.icu.text.MessageFormat;
 import android.text.TextPaint;
+import android.text.TextUtils;
 import android.text.TextUtils.TruncateAt;
 import android.util.AttributeSet;
 import android.util.Property;
@@ -805,7 +806,7 @@
                     invalidate();
                 }
             }
-            if (itemInfo.contentDescription != null) {
+            if (!TextUtils.isEmpty(itemInfo.contentDescription)) {
                 if (itemInfo.isDisabled()) {
                     setContentDescription(getContext().getString(R.string.disabled_app_label,
                             itemInfo.contentDescription));
diff --git a/src/com/android/launcher3/Utilities.java b/src/com/android/launcher3/Utilities.java
index b062b91..e0bb351 100644
--- a/src/com/android/launcher3/Utilities.java
+++ b/src/com/android/launcher3/Utilities.java
@@ -458,9 +458,10 @@
      * Trims the string, removing all whitespace at the beginning and end of the string.
      * Non-breaking whitespaces are also removed.
      */
+    @NonNull
     public static String trim(CharSequence s) {
         if (s == null) {
-            return null;
+            return "";
         }
 
         // Just strip any sequence of whitespace or java space characters from the beginning and end
diff --git a/src/com/android/launcher3/model/LoaderCursor.java b/src/com/android/launcher3/model/LoaderCursor.java
index 739a64a..ae5b66a 100644
--- a/src/com/android/launcher3/model/LoaderCursor.java
+++ b/src/com/android/launcher3/model/LoaderCursor.java
@@ -202,8 +202,7 @@
      * Returns the title or empty string
      */
     private String getTitle() {
-        String title = getString(titleIndex);
-        return TextUtils.isEmpty(title) ? "" : Utilities.trim(title);
+        return Utilities.trim(getString(titleIndex));
     }
 
     /**