app - currency - fix typo + prefer log over console

app/scripts/controllers/currency.js

@@ -44,14 +44,15 @@ class CurrencyController {
   }
 
   async updateConversionRate () {
+    let currentCurrency
     try {
-      const currentCurrency = this.getCurrentCurrency()
+      currentCurrency = this.getCurrentCurrency()
       const response = await fetch(`https://api.infura.io/v1/ticker/eth${currentCurrency.toLowerCase()}`)
       const parsedResponse = await response.json()
       this.setConversionRate(Number(parsedResponse.bid))
       this.setConversionDate(Number(parsedResponse.timestamp))
     } catch (err) {
-      console.warn(`MetaMask - Failed to query currency conversion:`, currentCurrency, err)
+      log.warn(`MetaMask - Failed to query currency conversion:`, currentCurrency, err)
       this.setConversionRate(0)
       this.setConversionDate('N/A')
     }