Dedup art-bootclasspath-fragment contents from sdk

Previously, the sdk duplicated the modules from the contents list of
the art-bootclasspath-fragment. That is no longer necessary as the
contents of bootclasspath_fragment modules are automatically added to
the sdk.

Bug: 177892522
Test: m art-module-sdk
      - check generated snapshot still contains core-oj, core-libart,
        etc.
Change-Id: I1a8720ff41981f31595a5d2d30164afd0a3a5764
diff --git a/build/sdk/Android.bp b/build/sdk/Android.bp
index db4ec34..a0f11ed 100644
--- a/build/sdk/Android.bp
+++ b/build/sdk/Android.bp
@@ -84,6 +84,7 @@
 
         android: {
             bootclasspath_fragments: [
+                // Adds the fragment and its contents to the sdk.
                 "art-bootclasspath-fragment",
             ],
 
@@ -91,20 +92,6 @@
                 "libcore-platform-compat-config",
             ],
 
-            // Create placeholder java_import prebuilts for the java boot libraries so that Soong
-            // can retrieve their dex implementation jars from the associated prebuilt_apex. All
-            // libraries listed in the exported_java_libs property of the ART apex (see
-            // packages/modules/ArtPrebuilt) must have a prebuilt provided by this sdk or one of
-            // the ART module_exports. Those java boot libraries which do not require a prebuilt for
-            // another reason, e.g. test, are listed here.
-            java_boot_libs: [
-                "apache-xml",
-                "bouncycastle",
-                "core-libart",
-                "core-oj",
-                "okhttp",
-            ],
-
             java_header_libs: [
                 // Needed by any module that builds against any non-numeric
                 // sdk_version other than "none".