Address error prone warning in PackageFunction by inlining variable initialization with its declaration.

RELNOTES: None
PiperOrigin-RevId: 259441919
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/PackageFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/PackageFunction.java
index 4ead9ee..0d66266 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/PackageFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/PackageFunction.java
@@ -396,9 +396,8 @@
         repositoryMappingValue.getRepositoryMapping();
 
     RootedPath buildFileRootedPath = packageLookupValue.getRootedPath(packageId);
-    FileValue buildFileValue = null;
 
-    buildFileValue = getBuildFileValue(env, buildFileRootedPath);
+    FileValue buildFileValue = getBuildFileValue(env, buildFileRootedPath);
     if (buildFileValue == null) {
       return null;
     }