Steps to reproduce the problem:
1. Open activity with webview ,do something and close the activity.

What is the expected behavior?
No memory leak should occur

What went wrong?
Memory leak occurs in 

Did this work before? N/A 

Chrome version: 67.0.3396.87  Channel: n/a
OS Version: 4.4.2
Flash Version: 

* com.***.CBActivity has leaked:
* GC ROOT android.os.ResultReceiver$MyResultReceiver.this$0
* references com.android.org.chromium.content.browser.ContentViewCore$3$1.this$1 (anonymous subclass of android.os.ResultReceiver)
* references com.android.org.chromium.content.browser.ContentViewCore$3.this$0 (anonymous implementation of com.android.org.chromium.content.browser.input.ImeAdapter$ImeAdapterDelegate)
* references com.android.org.chromium.content.browser.ContentViewCore.mContext
* leaks com.***.CBActivity instance

* Retaining: 128KB.
* Reference Key: 26e91c53-09a6-4175-aa72-11a1166fad83
* Device: LGE google Nexus 4 occam
* Android Version: 4.4.2 API: 19 LeakCanary: 1.5.4 74837f0
* Durations: watch=36055ms, gc=184ms, heap dump=647ms, analysis=30499ms

* Details:
* Instance of android.os.ResultReceiver$MyResultReceiver
|   this$0 = com.android.org.chromium.content.browser.ContentViewCore$3$1@1108423840 (0x421134a0)
|   mDescriptor = java.lang.String@1107986528 (0x420a8860)
|   mOwner = android.os.ResultReceiver$MyResultReceiver@1108423904 (0x421134e0)
|   mObject = 2013365896
* Instance of com.android.org.chromium.content.browser.ContentViewCore$3$1
|   this$1 = com.android.org.chromium.content.browser.ContentViewCore$3@1108007256 (0x420ad958)
|   mHandler = android.os.Handler@1108423872 (0x421134c0)
|   mReceiver = android.os.ResultReceiver$MyResultReceiver@1108423904 (0x421134e0)
|   mLocal = true
* Instance of com.android.org.chromium.content.browser.ContentViewCore$3
|   this$0 = com.android.org.chromium.content.browser.ContentViewCore@1109188056 (0x421cddd8)
* Instance of com.android.org.chromium.content.browser.ContentViewCore
|   static $staticOverhead = byte[24]@1097373529 (0x41689759)
|   static $assertionsDisabled = true
|   mAccessibilityInjector = com.android.org.chromium.content.browser.accessibility.JellyBeanAccessibilityInjector@1109310704 (0x421ebcf0)
|   mAccessibilityManager = android.view.accessibility.AccessibilityManager@1105423840 (0x41e36de0)
|   mAccessibilityScriptInjectionObserver = null
|   mActionMode = null
|   mAdapterInputConnectionFactory = com.android.org.chromium.content.browser.input.ImeAdapter$AdapterInputConnectionFactory@1107164400 (0x41fdfcf0)
|   mZoomManager = com.android.org.chromium.content.browser.ZoomManager@1109093592 (0x421b6cd8)
|   mBrowserAccessibilityManager = null
|   mContainerView = android.webkit.WebView@1109251552 (0x421dd5e0)
|   mContainerViewInternals = com.android.webview.chromium.WebViewChromium$InternalAccessAdapter@1109459208 (0x42210108)
|   mContentSettings = null
|   mContentViewClient = com.android.org.chromium.android_webview.AwContentsClient$AwContentViewClient@1107173736 (0x41fe2168)
|   mContentViewGestureHandler = com.android.org.chromium.content.browser.ContentViewGestureHandler@1109273664 (0x421e2c40)
|   mContext = com.***.CBActivity@1109414440 (0x42205228)
|   mDeferredHandleFadeInRunnable = null
|   mZoomControlsDelegate = com.android.org.chromium.android_webview.AwZoomControls@1108733792 (0x4215ef60)
|   mDownloadDelegate = null
|   mEndHandlePoint = com.android.org.chromium.content.browser.RenderCoordinates$NormalizedPoint@1109056336 (0x421adb50)
|   mFakeMouseMoveRunnable = null
|   mFocusPreOSKViewportRect = android.graphics.Rect@1109189896 (0x421ce508)
|   mGestureStateListener = com.android.org.chromium.android_webview.AwContents$AwGestureStateListener@1106566400 (0x41f4dd00)
|   mWebContentsObserver = com.android.org.chromium.content.browser.ContentViewCore$5@1109486728 (0x42216c88)
|   mViewAndroid = com.android.org.chromium.ui.ViewAndroid@1109076008 (0x421b2828)
|   mImeAdapter = com.android.org.chromium.content.browser.input.ImeAdapter@1109309856 (0x421eb9a0)
|   mInputConnection = com.android.org.chromium.content.browser.input.AdapterInputConnection@1109376256 (0x421fbd00)
|   mInsertionHandleController = com.android.org.chromium.content.browser.ContentViewCore$13@1105745576 (0x41e856a8)
|   mInsertionHandlePoint = com.android.org.chromium.content.browser.RenderCoordinates$NormalizedPoint@1109056360 (0x421adb68)
|   mJavaScriptInterfaces = java.util.HashMap@1109188344 (0x421cdef8)
|   mLastSelectedText = java.lang.String@1109000048 (0x4219ff70)
|   mVSyncProvider = null
|   mVSyncListener = null
|   mStartHandlePoint = com.android.org.chromium.content.browser.RenderCoordinates$NormalizedPoint@1109056312 (0x421adb38)
|   mSelectionHandleController = null
|   mRetainedJavaScriptObjects = java.util.HashSet@1107093512 (0x41fce808)
|   mRenderCoordinates = com.android.org.chromium.content.browser.RenderCoordinates@1109056256 (0x421adb00)
|   mPositionObserver = com.android.org.chromium.content.browser.ViewPositionObserver@1109073720 (0x421b1f38)
|   mPositionListener = com.android.org.chromium.content.browser.ContentViewCore$4@1107295752 (0x41fffe08)
|   mPopupZoomer = com.android.org.chromium.content.browser.PopupZoomer@1109280640 (0x421e4780)
|   mPid = 6961
|   mPhysicalBackingWidthPix = 768
|   mPhysicalBackingHeightPix = 1134
|   mPendingRendererFrame = true
|   mOverdrawBottomHeightPix = 0
|   mNeedUpdateOrientationChanged = false
|   mScrolledAndZoomedFocusedEditableNode = false
|   mSelectionEditable = false
|   mNeedAnimate = false
|   mNativeContentViewCore = 0
|   mUnfocusOnNextSizeChanged = false
|   mUnselectAllOnActionModeDismiss = false
|   mNativeAccessibilityEnabled = false
|   mVSyncListenerRegistered = false
|   mNativeAccessibilityAllowed = false
|   mVSyncSubscriberCount = 0
|   mHasSelection = false
|   mViewportHeightPix = 1134
|   mViewportSizeOffsetHeightPix = 0
|   mViewportSizeOffsetWidthPix = 0
|   mViewportWidthPix = 768
|   mHardwareAccelerated = true
|   mDidSignalVSyncUsingInputEvent = false
|   mAttachedToWindow = false
* Instance of com.***.CBActivity
|   static $staticOverhead = byte[72]@1107093577 (0x41fce849)
|   static e = null
|   static b = 3
|   static a = null
|   c = com.***.bean.CustomBrowserConfig@1109447040 (0x4220d180)
|   d = com.***.util.CBUtil@1109446640 (0x4220cff0)
|   f = com.***.Bank@1109444744 (0x4220c888)
|   g = null
|   h = null
|   mDelegate = android.support.v7.app.AppCompatDelegateImplV14@1109417984 (0x42206000)
|   mResources = null
|   mThemeId = 2131230870
|   mViewModelStore = null
|   mFragments = android.support.v4.app.FragmentController@1109415656 (0x422056e8)
|   mHandler = android.support.v4.app.FragmentActivity$1@1109415392 (0x422055e0)
|   mLoaderManager = null
|   mPendingFragmentActivityResults = android.support.v4.util.SparseArrayCompat@1109420824 (0x42206b18)
|   mNextCandidateRequestIndex = 0
|   mReallyStopped = true
|   mRequestedPermissionsFromFragment = false
|   mResumed = false
|   mRetaining = false
|   mStopped = true
|   mCreated = true
|   mStartedActivityFromFragment = false
|   mStartedIntentSenderFromFragment = false
|   mExtraDataMap = android.support.v4.util.SimpleArrayMap@1109415032 (0x42205478)
|   mLifecycleRegistry = android.arch.lifecycle.LifecycleRegistry@1109415056 (0x42205490)
|   mActionBar = null
|   mActivityInfo = android.content.pm.ActivityInfo@1109412432 (0x42204a50)
|   mAllLoaderManagers = android.util.ArrayMap@1109451936 (0x4220e4a0)
|   mApplication = com.payu.testapp.CustomApp@1105131776 (0x41def900)
|   mWindowManager = android.view.WindowManagerImpl@1109417832 (0x42205f68)
|   mWindow = com.android.internal.policy.impl.PhoneWindow@1109416320 (0x42205980)
|   mUiThread = java.lang.Thread@1095912616 (0x41524ca8)
|   mTranslucentCallback = null
|   mComponent = android.content.ComponentName@1109412152 (0x42204938)
|   mToken = android.os.BinderProxy@1109412336 (0x422049f0)
|   mContainer = android.app.Activity$1@1109414904 (0x422053f8)
|   mCurrentConfig = android.content.res.Configuration@1109416184 (0x422058f8)
|   mDecor = null
|   mTitle = java.lang.String@1105334744 (0x41e211d8)
|   mDefaultKeySsb = null
|   mSearchManager = null
|   mResultData = null
|   mEmbeddedID = null
|   mParent = null
|   mMenuInflater = null
|   mFragments = android.app.FragmentManagerImpl@1109414784 (0x42205380)
|   mHandler = android.os.Handler@1109415000 (0x42205458)
|   mManagedDialogs = null
|   mInstanceTracker = android.os.StrictMode$InstanceTracker@1109414944 (0x42205420)
|   mInstrumentation = android.app.Instrumentation@1105127520 (0x41dee860)
|   mIntent = android.content.Intent@1109412008 (0x422048a8)
|   mLastNonConfigurationInstances = null
|   mLoaderManager = null
|   mManagedCursors = java.util.ArrayList@1109414920 (0x42205408)
|   mMainThread = android.app.ActivityThread@1105107096 (0x41de9898)
|   mLoadersStarted = false
|   mIdent = 1112835304
|   mFinished = true
|   mEnableDefaultActionBarUp = false
|   mResultCode = 0
|   mDoReportFullyDrawn = false
|   mResumed = false
|   mDestroyed = true
|   mStartedActivity = false
|   mStopped = true
|   mTemporaryPause = false
|   mDefaultKeyMode = 0
|   mTitleColor = 0
|   mTitleReady = true
|   mConfigChangeFlags = 0
|   mCheckedForLoaderManager = true
|   mChangingConfigurations = false
|   mVisibleFromClient = true
|   mVisibleFromServer = true
|   mChangeCanvasToTranslucent = false
|   mWindowAdded = true
|   mCalled = true
|   mBase = android.app.ContextImpl@1109415672 (0x422056f8)
|   mInflater = com.android.internal.policy.impl.PhoneLayoutInflater@1109417424 (0x42205dd0)
|   mOverrideConfiguration = null
|   mResources = android.content.res.Resources@1105124264 (0x41dedba8)
|   mTheme = android.content.res.Resources$Theme@1109417856 (0x42205f80)
|   mThemeResource = 2131230870
|   mBase = android.app.ContextImpl@1109415672 (0x422056f8)
* Excluded Refs:
| Field: android.app.ActivityThread$ActivityClientRecord.nextIdle
| Field: android.widget.Editor$EasyEditSpanController.this$0
| Field: android.widget.Editor$SpanController.this$0
| Field: android.os.Message.obj
| Field: android.os.Message.next
| Field: android.os.Message.target
| Field: android.view.inputmethod.InputMethodManager.mNextServedView
| Field: android.view.inputmethod.InputMethodManager.mServedView
| Field: android.view.inputmethod.InputMethodManager.mServedInputConnection
| Field: android.view.inputmethod.InputMethodManager.mCurRootView
| Field: android.animation.LayoutTransition$1.val$parent
| Field: android.view.textservice.SpellCheckerSession$1.this$0
| Field: android.support.v7.internal.widget.ActivityChooserModel.mActivityChoserModelPolicy
| Field: android.widget.ActivityChooserModel.mActivityChoserModelPolicy
| Field: android.speech.SpeechRecognizer$InternalListener.this$0
| Field: android.accounts.AccountManager$AmsTask$Response.this$1
| Field: android.media.MediaScannerConnection.mContext
| Field: android.os.UserManager.mContext
| Field: android.appwidget.AppWidgetHost$Callbacks.this$0
| Field: android.media.AudioManager$1.this$0
| Field: android.widget.Editor$Blink.this$0
| Field: android.net.ConnectivityManager.sInstance
| Field: android.view.Choreographer$FrameDisplayEventReceiver.mMessageQueue (always)
| Static field: android.text.TextLine.sCached
| Static field: android.widget.BubblePopupHelper.sHelper
| Thread:FinalizerWatchdogDaemon (always)
| Thread:main (always)
| Thread:LeakCanary-Heap-Dump (always)
| Class:java.lang.ref.WeakReference (always)
| Class:java.lang.ref.SoftReference (always)
| Class:java.lang.ref.PhantomReference (always)
| Class:java.lang.ref.Finalizer (always)
| Class:java.lang.ref.FinalizerReference (always)