Fix build breakages when WITHOUT_CHECK_API=true

Bug: 158578354
Test: export WITHOUT_CHECK_API=true
      m checkbuild
Change-Id: I7b5fff40b870c9d754f779ff1c3314bac7e42440
Merged-In: I7b5fff40b870c9d754f779ff1c3314bac7e42440
diff --git a/java/sdk_library.go b/java/sdk_library.go
index 7ce0912..26bd670 100644
--- a/java/sdk_library.go
+++ b/java/sdk_library.go
@@ -2188,8 +2188,12 @@
 			properties.Jars = jars
 			properties.SdkVersion = sdk.sdkVersionForStubsLibrary(ctx.SdkModuleContext(), apiScope)
 			properties.StubsSrcJar = paths.stubsSrcJar.Path()
-			properties.CurrentApiFile = paths.currentApiFilePath.Path()
-			properties.RemovedApiFile = paths.removedApiFilePath.Path()
+			if paths.currentApiFilePath.Valid() {
+				properties.CurrentApiFile = paths.currentApiFilePath.Path()
+			}
+			if paths.removedApiFilePath.Valid() {
+				properties.RemovedApiFile = paths.removedApiFilePath.Path()
+			}
 			s.Scopes[apiScope] = properties
 		}
 	}