Remove components entry, guard QResizeObserver (quasarframework#2258)

Author: pdanpdan

src/components/datetime/QDatetimePicker.mat.js

@@ -19,9 +19,6 @@ export default {
     disable: Boolean,
     readonly: Boolean
   },
-  components: {
-    QBtn
-  },
   directives: {
     Ripple
   },

src/components/input/QInput.js

@@ -11,11 +11,6 @@ import QIcon from '../icon/QIcon.js'
 export default {
   name: 'QInput',
   mixins: [FrameMixin, InputMixin],
-  components: {
-    QInputFrame,
-    QSpinner,
-    QResizeObservable
-  },
   props: {
     value: { required: true },
     type: {

src/components/observables/QResizeObservable.js

@@ -94,7 +94,7 @@ export default {
     clearTimeout(this.timer)
 
     if (this.hasObserver) {
-      this.observer.unobserve(this.$el.parentNode)
+      this.$el.parentNode && this.observer.unobserve(this.$el.parentNode)
       return
     }
 

src/components/option-group/QOptionGroup.js

@@ -3,14 +3,15 @@ import QCheckbox from '../checkbox/QCheckbox.js'
 import QToggle from '../toggle/QToggle.js'
 import ParentFieldMixin from '../../mixins/parent-field.js'
 
+const components = {
+  radio: QRadio,
+  checkbox: QCheckbox,
+  toggle: QToggle
+}
+
 export default {
   name: 'QOptionGroup',
   mixins: [ParentFieldMixin],
-  components: {
-    QRadio,
-    QCheckbox,
-    QToggle
-  },
   props: {
     value: {
       required: true
@@ -35,7 +36,7 @@ export default {
   },
   computed: {
     component () {
-      return `q-${this.type}`
+      return components[this.type]
     },
     model () {
       return Array.isArray(this.value) ? this.value.slice() : this.value

src/components/select/QSelect.js

@@ -18,18 +18,6 @@ function defaultFilterFn (terms, obj) {
 export default {
   name: 'QSelect',
   mixins: [FrameMixin, KeyboardSelectionMixin],
-  components: {
-    QSearch,
-    QPopover,
-    QList,
-    QItemWrapper,
-    QCheckbox,
-    QRadio,
-    QToggle,
-    QIcon,
-    QInputFrame,
-    QChip
-  },
   props: {
     filter: [Function, Boolean],
     filterPlaceholder: String,

src/components/stepper/QStepper.js

@@ -3,9 +3,6 @@ import frameDebounce from '../../utils/frame-debounce.js'
 
 export default {
   name: 'QStepper',
-  components: {
-    StepTab
-  },
   props: {
     value: [Number, String],
     color: {

src/components/stepper/StepTab.js

@@ -3,9 +3,6 @@ import Ripple from '../../directives/ripple.js'
 
 export default {
   name: 'QStepTab',
-  components: {
-    QIcon
-  },
   directives: {
     Ripple
   },