apex: dedup jni_libs when generating apex_manifest

When we package both 32/62, there could be two instances of the same
library. We need to dedup the list of jni_libs.

Bug: n/a
Test: m com.android.cronet (which uses jni_libs)
      check apex_manifest.pb
Change-Id: I9a9f42f0f5219ab7bc50d945b54113b5d823b7f3

apex/builder.go

@@ -193,7 +193,7 @@ func (a *apexBundle) buildManifest(ctx android.ModuleContext, provideNativeLibs,
 	// collect jniLibs. Notice that a.filesInfo is already sorted
 	var jniLibs []string
 	for _, fi := range a.filesInfo {
-		if fi.isJniLib {
+		if fi.isJniLib && !android.InList(fi.Stem(), jniLibs) {
 			jniLibs = append(jniLibs, fi.Stem())
 		}
 	}