Remove `--incompatible_disallow_data_transition` flag

https://github.com/bazelbuild/bazel/issues/6153

RELNOTES: None.
PiperOrigin-RevId: 240442015
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/skylark/SkylarkAttr.java b/src/main/java/com/google/devtools/build/lib/analysis/skylark/SkylarkAttr.java
index ee19167..ebff96a 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/skylark/SkylarkAttr.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/skylark/SkylarkAttr.java
@@ -259,17 +259,7 @@
             ast.getLocation(),
             "late-bound attributes must not have a split configuration transition");
       }
-      if (trans.equals("data")) {
-        // This used to apply the "disable LIPO" (a.k.a. "data") transition. But now that LIPO is
-        // turned down this is a noop. Still, there are cfg = "data"' references in the depot. So
-        // we have to remove them via b/28688645 before we can remove this path.
-        if (env.getSemantics().incompatibleDisallowDataTransition()) {
-          throw new EvalException(ast.getLocation(),
-              "Using cfg = \"data\" on an attribute is a noop and no longer supported. Please "
-                  + "remove it. You can use --incompatible_disallow_data_transition=false to "
-                  + "temporarily disable this check.");
-        }
-      } else if (trans.equals("host")) {
+      if (trans.equals("host")) {
         builder.cfg(HostTransition.INSTANCE);
       } else if (trans instanceof SplitTransition) {
         builder.cfg((SplitTransition) trans);
@@ -293,8 +283,7 @@
         builder.cfg(new StarlarkAttributeTransitionProvider(starlarkDefinedTransition));
       } else if (!trans.equals("target")) {
         // TODO(b/121134880): update error message when starlark build configurations is ready.
-        throw new EvalException(
-            ast.getLocation(), "cfg must be either 'data', 'host', or 'target'.");
+        throw new EvalException(ast.getLocation(), "cfg must be either 'host' or 'target'.");
       }
     }
 
diff --git a/src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java b/src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java
index 59b6376..1a2c2e9 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java
@@ -252,18 +252,6 @@
   public boolean incompatibleDisableThirdPartyLicenseChecking;
 
   @Option(
-      name = "incompatible_disallow_data_transition",
-      defaultValue = "true",
-      documentationCategory = OptionDocumentationCategory.STARLARK_SEMANTICS,
-      effectTags = {OptionEffectTag.BUILD_FILE_SEMANTICS},
-      metadataTags = {
-        OptionMetadataTag.INCOMPATIBLE_CHANGE,
-        OptionMetadataTag.TRIGGERED_BY_ALL_INCOMPATIBLE_CHANGES
-      },
-      help = "If set to true, rule attributes cannot set 'cfg = \"data\"', which is a noop.")
-  public boolean incompatibleDisallowDataTransition;
-
-  @Option(
       name = "incompatible_disallow_dict_plus",
       defaultValue = "true",
       documentationCategory = OptionDocumentationCategory.STARLARK_SEMANTICS,
@@ -560,7 +548,6 @@
         .incompatibleDisableThirdPartyLicenseChecking(incompatibleDisableThirdPartyLicenseChecking)
         .incompatibleDisableDeprecatedAttrParams(incompatibleDisableDeprecatedAttrParams)
         .incompatibleDisableObjcProviderResources(incompatibleDisableObjcProviderResources)
-        .incompatibleDisallowDataTransition(incompatibleDisallowDataTransition)
         .incompatibleDisallowDictPlus(incompatibleDisallowDictPlus)
         .incompatibleDisallowFileType(incompatibleDisallowFileType)
         .incompatibleDisallowLegacyJavaInfo(incompatibleDisallowLegacyJavaInfo)
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/StarlarkSemantics.java b/src/main/java/com/google/devtools/build/lib/syntax/StarlarkSemantics.java
index c60216d..abddc4f 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/StarlarkSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/StarlarkSemantics.java
@@ -140,8 +140,6 @@
 
   public abstract boolean incompatibleDisableObjcProviderResources();
 
-  public abstract boolean incompatibleDisallowDataTransition();
-
   public abstract boolean incompatibleDisallowDictPlus();
 
   public abstract boolean incompatibleDisallowFileType();
@@ -214,7 +212,6 @@
           .incompatibleDisableThirdPartyLicenseChecking(false)
           .incompatibleDisableDeprecatedAttrParams(false)
           .incompatibleDisableObjcProviderResources(false)
-          .incompatibleDisallowDataTransition(true)
           .incompatibleDisallowDictPlus(true)
           .incompatibleDisallowFileType(true)
           .incompatibleDisallowLegacyJavaProvider(false)
@@ -270,8 +267,6 @@
 
     public abstract Builder incompatibleDisableObjcProviderResources(boolean value);
 
-    public abstract Builder incompatibleDisallowDataTransition(boolean value);
-
     public abstract Builder incompatibleDisallowDictPlus(boolean value);
 
     public abstract Builder incompatibleDisallowFileType(boolean value);
diff --git a/src/test/java/com/google/devtools/build/lib/packages/SkylarkSemanticsConsistencyTest.java b/src/test/java/com/google/devtools/build/lib/packages/SkylarkSemanticsConsistencyTest.java
index a7b732b..ff7874f 100644
--- a/src/test/java/com/google/devtools/build/lib/packages/SkylarkSemanticsConsistencyTest.java
+++ b/src/test/java/com/google/devtools/build/lib/packages/SkylarkSemanticsConsistencyTest.java
@@ -138,7 +138,6 @@
         "--incompatible_disable_deprecated_attr_params=" + rand.nextBoolean(),
         "--incompatible_disable_objc_provider_resources=" + rand.nextBoolean(),
         "--incompatible_disable_third_party_license_checking=" + rand.nextBoolean(),
-        "--incompatible_disallow_data_transition=" + rand.nextBoolean(),
         "--incompatible_disallow_dict_plus=" + rand.nextBoolean(),
         "--incompatible_disallow_filetype=" + rand.nextBoolean(),
         "--incompatible_disallow_legacy_javainfo=" + rand.nextBoolean(),
@@ -185,7 +184,6 @@
         .incompatibleDisableDeprecatedAttrParams(rand.nextBoolean())
         .incompatibleDisableObjcProviderResources(rand.nextBoolean())
         .incompatibleDisableThirdPartyLicenseChecking(rand.nextBoolean())
-        .incompatibleDisallowDataTransition(rand.nextBoolean())
         .incompatibleDisallowDictPlus(rand.nextBoolean())
         .incompatibleDisallowFileType(rand.nextBoolean())
         .incompatibleDisallowLegacyJavaInfo(rand.nextBoolean())
diff --git a/src/test/java/com/google/devtools/build/lib/skylark/SkylarkRuleClassFunctionsTest.java b/src/test/java/com/google/devtools/build/lib/skylark/SkylarkRuleClassFunctionsTest.java
index f14a303..382c7bb 100644
--- a/src/test/java/com/google/devtools/build/lib/skylark/SkylarkRuleClassFunctionsTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skylark/SkylarkRuleClassFunctionsTest.java
@@ -594,17 +594,9 @@
 
   @Test
   public void incompatibleDataTransition() throws Exception {
-    ev =
-        createEvaluationTestCase(
-            StarlarkSemantics.DEFAULT_SEMANTICS
-                .toBuilder()
-                .incompatibleDisallowDataTransition(true)
-                .build());
-    ev.initialize();
     EvalException expected =
         assertThrows(EvalException.class, () -> eval("attr.label(cfg = 'data')"));
-    assertThat(expected).hasMessageThat().contains(
-        "Using cfg = \"data\" on an attribute is a noop and no longer supported");
+    assertThat(expected).hasMessageThat().contains("cfg must be either 'host' or 'target'");
   }
 
   @Test