What does the logcat warning “Unknown element under <manifest>: metadata” mean?

Question

When starting a recently installed application, I find these Warningmessages in logcat:

W/PackageManager( 1233): Couldn't remove dex file for package:  at location /data/app/xx.yy.zz-1/base.apk, retcode=-1
I/SmartHeartBeat( 1233): listenAppUpdate, package: xx.yy.zz has been Updated
W/PackageParser( 2909): Unknown element under <manifest>: meta-data at /storage/emulated/0/xxx/zz.apk Binary XML file line #143

Trying to track down an abusive meta-datatag element Binary XML file line #143, I find the following:

# aapt l -a zz.apk

AndroidManifest.xml
META-INF/CERT.RSA
META-INF/CERT.SF
META-INF/MANIFEST.MF
...
Android manifest:
N: android=http://schemas.android.com/apk/res/android
  E: manifest (line=2)
    ...
    A: platformBuildVersionCode=(type 0x10)0x19 (Raw: "25")
    A: platformBuildVersionName="7.1.1" (Raw: "7.1.1")
    ...
    E: meta-data (line=143)
      A: android:name(0x01010003)="android.support.VERSION" (Raw: "android.support.VERSION")
      A: android:value(0x01010024)="25.3.1" (Raw: "25.3.1")
...

But I have nothing of the kind in mine AndroidManifest.xml, and the only link to "25.3.1" is in my file gradle.build, which is the dependency lines for the Android support libraries:

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:support-v4:25.3.1'
    ...
}

What is the problem and why does this warning occur? (How to resolve it?)

Answer 1

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