Fix nullability lint issue in EmojiMetadata

Bug: 236341259
Relnote: EmojiMetadata typeface specified as non null
Test: N/A
Change-Id: Ic727f852ab6a1ca1e799eea8b1e2919473613ac5

diff --git a/emoji/emoji/api/restricted_current.txt b/emoji/emoji/api/restricted_current.txt
index 95072c9..dd1967a 100644
--- a/emoji/emoji/api/restricted_current.txt
+++ b/emoji/emoji/api/restricted_current.txt

@@ -85,7 +85,7 @@
     method public short getHeight();
     method public int getId();
     method public short getSdkAdded();
-    method public android.graphics.Typeface! getTypeface();
+    method public android.graphics.Typeface getTypeface();
     method public short getWidth();
     method public boolean isDefaultEmoji();
     method public void setHasGlyph(boolean);

diff --git a/emoji/emoji/src/main/java/androidx/emoji/text/EmojiMetadata.java b/emoji/emoji/src/main/java/androidx/emoji/text/EmojiMetadata.java
index ea0a187..5b61e35 100644
--- a/emoji/emoji/src/main/java/androidx/emoji/text/EmojiMetadata.java
+++ b/emoji/emoji/src/main/java/androidx/emoji/text/EmojiMetadata.java

@@ -117,7 +117,7 @@
     /**
      * @return return typeface to be used to render this metadata
      */
-    public Typeface getTypeface() {
+    public @NonNull Typeface getTypeface() {
         return mMetadataRepo.getTypeface();
     }
 

diff --git a/emoji/emoji/src/main/java/androidx/emoji/text/MetadataRepo.java b/emoji/emoji/src/main/java/androidx/emoji/text/MetadataRepo.java
index 0c5bb01..75df74a 100644
--- a/emoji/emoji/src/main/java/androidx/emoji/text/MetadataRepo.java
+++ b/emoji/emoji/src/main/java/androidx/emoji/text/MetadataRepo.java

@@ -63,7 +63,7 @@
     /**
      * Typeface to be used to render emojis.
      */
-    private final Typeface mTypeface;
+    private final @NonNull Typeface mTypeface;
 
     /**
      * Constructor used for tests.
@@ -72,7 +72,7 @@
      */
     @RestrictTo(LIBRARY_GROUP_PREFIX)
     MetadataRepo() {
-        mTypeface = null;
+        mTypeface = Typeface.DEFAULT;
         mMetadataList = null;
         mRootNode = new Node(DEFAULT_ROOT_SIZE);
         mEmojiCharArray = new char[0];
@@ -149,7 +149,7 @@
      * @hide
      */
     @RestrictTo(LIBRARY_GROUP_PREFIX)
-    Typeface getTypeface() {
+    @NonNull Typeface getTypeface() {
         return mTypeface;
     }