Flip --incompatible_disallow_java_import_exports flag

RELNOTES[inc]: java_import to require that the jars attribute be non-empty (#16385)

PiperOrigin-RevId: 486976650
Change-Id: If28c1ee0476d94a3359806ab04d61427a2d4da6b

Author: kotlaja

src/main/java/com/google/devtools/build/lib/rules/java/JavaOptions.java

@@ -596,7 +596,7 @@ public ImportDepsCheckingLevelConverter() {
 
   @Option(
       name = "incompatible_disallow_java_import_empty_jars",
-      defaultValue = "false",
+      defaultValue = "true",
       documentationCategory = OptionDocumentationCategory.UNDOCUMENTED,
       effectTags = {OptionEffectTag.UNKNOWN},
       metadataTags = {OptionMetadataTag.INCOMPATIBLE_CHANGE},

src/test/shell/integration/java_integration_test.sh

@@ -843,7 +843,7 @@ java_binary(
 EOF
   bazel build --incompatible_disallow_java_import_empty_jars=0 //$pkg/java/hello:hello //$pkg/java/hello:hello_deploy.jar >& "$TEST_log" \
       || fail "Expected success"
-  bazel run //$pkg/java/hello:hello -- --singlejar >& "$TEST_log"
+  bazel run --incompatible_disallow_java_import_empty_jars=0 //$pkg/java/hello:hello -- --singlejar >& "$TEST_log"
   expect_log "Hello World!"
 }