Add empty string check for resource loading.

When a resource name is invalid or empty we should return null.

Bug: 260244331
Test: run_tests.sh for regression.
Change-Id: I70dfff9f2cc9a7a0119d99b17f5359c18f766068
(cherry picked from commit 82120bb6b8d9f496393a2795c02bc769aa327bcb)
Merged-In: I70dfff9f2cc9a7a0119d99b17f5359c18f766068

3 files changed, 11 insertions, 2 deletions

diff --git a/bridge/src/android/graphics/Typeface_Delegate.java b/bridge/src/android/graphics/Typeface_Delegate.java
index 2d343a58ca..4568876d1d 100644
--- a/bridge/src/android/graphics/Typeface_Delegate.java
+++ b/bridge/src/android/graphics/Typeface_Delegate.java
@@ -61,6 +61,11 @@ public final class Typeface_Delegate {
         if (typeface != null) {
             return typeface;
         }
+
+        if (path.isBlank()) {
+            return null;
+        }
+
         String lowerCaseValue = path.toLowerCase();
         if (lowerCaseValue.endsWith(AndroidConstants.DOT_XML)) {
             // create a block parser for the file
@@ -113,4 +118,4 @@ public final class Typeface_Delegate {
     /*package*/ static Typeface create(Typeface family, int style, boolean isItalic) {
         return Typeface.create_Original(family, style, isItalic);
     }
-}
\ No newline at end of file
+}
diff --git a/bridge/src/android/graphics/fonts/Font_Builder_Delegate.java b/bridge/src/android/graphics/fonts/Font_Builder_Delegate.java
index 46d3dcf160..c21a4f1722 100644
--- a/bridge/src/android/graphics/fonts/Font_Builder_Delegate.java
+++ b/bridge/src/android/graphics/fonts/Font_Builder_Delegate.java
@@ -47,6 +47,10 @@ public class Font_Builder_Delegate {
     /*package*/ static ByteBuffer createBuffer(@NonNull AssetManager am, @NonNull String path,
             boolean isAsset, int cookie) throws IOException {
 
+        if (path.isBlank()) {
+            return null;
+        }
+
         try (InputStream assetStream = isAsset ? am.open(path, AssetManager.ACCESS_BUFFER)
                 : am.openNonAsset(cookie, path, AssetManager.ACCESS_BUFFER)) {
 
diff --git a/bridge/src/com/android/layoutlib/bridge/impl/ResourceHelper.java b/bridge/src/com/android/layoutlib/bridge/impl/ResourceHelper.java
index c6888d0998..87bed3d967 100644
--- a/bridge/src/com/android/layoutlib/bridge/impl/ResourceHelper.java
+++ b/bridge/src/com/android/layoutlib/bridge/impl/ResourceHelper.java
@@ -481,7 +481,7 @@ public final class ResourceHelper {
      */
     public static Typeface getFont(String fontName, BridgeContext context, Theme theme, boolean
             isFramework) {
-        if (fontName == null) {
+        if (fontName == null || fontName.isBlank()) {
             return null;
         }