fix(VDialog.js): fixed event variable ref in onFocusin

[mcculleydj]

Description

onFocusin method in VDialog.js uses e as an argument representing the event and then uses event in the function body.

Motivation and Context

Have observed event is undefined error in Firefox whenever an input element is focused inside of a v-dialog.

How Has This Been Tested?

I used the dialog with form example from the docs. Observed the error in Firefox without my fix and observed no error with my fix.

Markup:

<template>
  <v-app>
<v-layout row justify-center>
    <v-dialog v-model="dialog" persistent max-width="600px">
      <template v-slot:activator="{ on }">
        <v-btn color="primary" dark v-on="on">Open Dialog</v-btn>
      </template>
      <v-card>
        <v-card-title>
          <span class="headline">User Profile</span>
        </v-card-title>
        <v-card-text>
          <v-container grid-list-md>
            <v-layout wrap>
              <v-flex xs12 sm6 md4>
                <v-text-field label="Legal first name*" required></v-text-field>
              </v-flex>
              <v-flex xs12 sm6 md4>
                <v-text-field label="Legal middle name" hint="example of helper text only on focus"></v-text-field>
              </v-flex>
              <v-flex xs12 sm6 md4>
                <v-text-field
                  label="Legal last name*"
                  hint="example of persistent helper text"
                  persistent-hint
                  required
                ></v-text-field>
              </v-flex>
              <v-flex xs12>
                <v-text-field label="Email*" required></v-text-field>
              </v-flex>
              <v-flex xs12>
                <v-text-field label="Password*" type="password" required></v-text-field>
              </v-flex>
              <v-flex xs12 sm6>
                <v-select
                  :items="['0-17', '18-29', '30-54', '54+']"
                  label="Age*"
                  required
                ></v-select>
              </v-flex>
              <v-flex xs12 sm6>
                <v-autocomplete
                  :items="['Skiing', 'Ice hockey', 'Soccer', 'Basketball', 'Hockey', 'Reading', 'Writing', 'Coding', 'Basejump']"
                  label="Interests"
                  multiple
                ></v-autocomplete>
              </v-flex>
            </v-layout>
          </v-container>
          <small>*indicates required field</small>
        </v-card-text>
        <v-card-actions>
          <v-spacer></v-spacer>
          <v-btn color="blue darken-1" flat @click="dialog = false">Close</v-btn>
          <v-btn color="blue darken-1" flat @click="dialog = false">Save</v-btn>
        </v-card-actions>
      </v-card>
    </v-dialog>
  </v-layout>
  </v-app>
</template>

<script>
  export default {
    data: () => ({
      dialog: false
    })
  }
</script>

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Improvement/refactoring (non-breaking change that doesn't add any feature but make things better)

Checklist:

• The PR title is no longer than 64 characters.
• The PR is submitted to the correct branch (master for bug fixes and documentation updates, dev for new features and breaking changes).
• My code follows the code style of this project.
• I've added relevant changes to the documentation (applies to new features and breaking changes in core library)

[codecov]

Codecov Report

Merging #7498 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master    #7498   +/-   ##
=======================================
  Coverage   85.43%   85.43%           
=======================================
  Files         298      298           
  Lines        7221     7221           
  Branches     1804     1804           
=======================================
  Hits         6169     6169           
  Misses        956      956           
  Partials       96       96

Impacted Files	Coverage Δ
packages/vuetify/src/components/VDialog/VDialog.js	71.28% <0%> (ø)	⬆️

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[KaelWD]

lmao how did I do that

[CesarGomezTissini]

The same issue occurs with Bottom Sheets.