Put main repo remapping behind a flag.

RELNOTES: None
PiperOrigin-RevId: 207801155
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkSemantics.java b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkSemantics.java
index 5893ac49..85f6d4d 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkSemantics.java
@@ -45,6 +45,8 @@
 
   public abstract boolean experimentalEnableRepoMapping();
 
+  public abstract boolean experimentalRemapMainRepo();
+
   public abstract boolean incompatibleBzlDisallowLoadAfterStatement();
 
   public abstract boolean incompatibleDepsetIsNotIterable();
@@ -102,6 +104,7 @@
           // <== Add new options here in alphabetic order ==>
           .experimentalCcSkylarkApiEnabledPackages(ImmutableList.of())
           .experimentalEnableRepoMapping(false)
+          .experimentalRemapMainRepo(false)
           .incompatibleBzlDisallowLoadAfterStatement(false)
           .incompatibleDepsetIsNotIterable(false)
           .incompatibleDepsetUnion(false)
@@ -133,6 +136,8 @@
 
     public abstract Builder experimentalEnableRepoMapping(boolean value);
 
+    public abstract Builder experimentalRemapMainRepo(boolean value);
+
     public abstract Builder incompatibleBzlDisallowLoadAfterStatement(boolean value);
 
     public abstract Builder incompatibleDepsetIsNotIterable(boolean value);