remove some redundant viewpager variables

app/src/main/kotlin/com/simplemobiletools/gallery/activities/ViewPagerActivity.kt

@@ -2,7 +2,6 @@ package com.simplemobiletools.gallery.activities
 
 import android.app.Activity
 import android.content.Intent
-import android.content.res.Configuration
 import android.database.Cursor
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
@@ -13,7 +12,6 @@ import android.os.Build
 import android.os.Bundle
 import android.provider.MediaStore
 import android.support.v4.view.ViewPager
-import android.util.DisplayMetrics
 import android.view.Menu
 import android.view.MenuItem
 import android.view.View
@@ -51,12 +49,6 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
     private var mShowAll = false
     private var mRotationDegrees = 0f
 
-    companion object {
-        var screenWidth = 0
-        var screenHeight = 0
-        var screenDensity = 0f
-    }
-
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_medium)
@@ -66,7 +58,6 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
             return
         }
 
-        measureScreen()
         val uri = intent.data
         if (uri != null) {
             var cursor: Cursor? = null
@@ -166,19 +157,6 @@ class ViewPagerActivity : SimpleActivity(), ViewPager.OnPageChangeListener, View
         return true
     }
 
-    override fun onConfigurationChanged(newConfig: Configuration?) {
-        super.onConfigurationChanged(newConfig)
-        measureScreen()
-    }
-
-    private fun measureScreen() {
-        val metrics = DisplayMetrics()
-        windowManager.defaultDisplay.getMetrics(metrics)
-        screenWidth = metrics.widthPixels
-        screenHeight = metrics.heightPixels
-        screenDensity = metrics.density
-    }
-
     private fun updatePagerItems() {
         val pagerAdapter = MyPagerAdapter(this, supportFragmentManager, mMedia)
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1 && !isDestroyed) {