Change identicon seed algo to match Metamask

Author: jmrossy

src/components/Identicon.tsx

@@ -1,5 +1,4 @@
 import jazzicon from '@metamask/jazzicon'
-import { BigNumber } from 'ethers'
 import { PureComponent } from 'react'
 import { Styles } from 'src/styles/types'
 import { isValidAddress, normalizeAddress } from 'src/utils/addresses'
@@ -10,8 +9,10 @@ type Props = {
   styles?: Styles
 }
 
+// This should match metamask: https://github.com/MetaMask/metamask-extension/blob/master/ui/helpers/utils/icon-factory.js#L84
 function addressToSeed(address: string) {
-  return BigNumber.from(normalizeAddress(address).slice(0, 8)).toNumber()
+  const addrStub = normalizeAddress(address).slice(2, 10)
+  return parseInt(addrStub, 16)
 }
 
 export class Identicon extends PureComponent<Props> {