Don't run the outliner when compiling to classfiles.

Bug: 143550696
Change-Id: I989a1d8430d563495118533d39fc6b94bed1d6f4
diff --git a/src/main/java/com/android/tools/r8/R8Command.java b/src/main/java/com/android/tools/r8/R8Command.java
index f4b3763..6a65f79 100644
--- a/src/main/java/com/android/tools/r8/R8Command.java
+++ b/src/main/java/com/android/tools/r8/R8Command.java
@@ -859,6 +859,13 @@
       internal.assertionProcessing = AssertionProcessing.LEAVE;
     }
 
+    // When generating class files the build is "intermediate" and we cannot pollute the namespace
+    // with the a hard-coded outline class. Doing so would prohibit subsequent merging of two
+    // R8 produced libraries.
+    if (internal.isGeneratingClassFiles()) {
+      internal.outline.enabled = false;
+    }
+
     // EXPERIMENTAL flags.
     assert !internal.forceProguardCompatibility;
     internal.forceProguardCompatibility = forceProguardCompatibility;