remove unused sufficient balance method (#11381)

this method relied on gasPrice being present and is safe to remove

app/scripts/lib/util.js

@@ -1,4 +1,3 @@
-import { strict as assert } from 'assert';
 import extension from 'extensionizer';
 import { stripHexPrefix } from 'ethereumjs-util';
 import BN from 'bn.js';
@@ -70,39 +69,6 @@ const getPlatform = (_) => {
   return PLATFORM_FIREFOX;
 };
 
-/**
- * Checks whether a given balance of ETH, represented as a hex string, is sufficient to pay a value plus a gas fee
- *
- * @param {Object} txParams - Contains data about a transaction
- * @param {string} txParams.gas - The gas for a transaction
- * @param {string} txParams.gasPrice - The price per gas for the transaction
- * @param {string} txParams.value - The value of ETH to send
- * @param {string} hexBalance - A balance of ETH represented as a hex string
- * @returns {boolean} Whether the balance is greater than or equal to the value plus the value of gas times gasPrice
- *
- */
-function sufficientBalance(txParams, hexBalance) {
-  // validate hexBalance is a hex string
-  assert.equal(
-    typeof hexBalance,
-    'string',
-    'sufficientBalance - hexBalance is not a hex string',
-  );
-  assert.equal(
-    hexBalance.slice(0, 2),
-    '0x',
-    'sufficientBalance - hexBalance is not a hex string',
-  );
-
-  const balance = hexToBn(hexBalance);
-  const value = hexToBn(txParams.value);
-  const gasLimit = hexToBn(txParams.gas);
-  const gasPrice = hexToBn(txParams.gasPrice);
-
-  const maxCost = value.add(gasLimit.mul(gasPrice));
-  return balance.gte(maxCost);
-}
-
 /**
  * Converts a hex string to a BN object
  *
@@ -183,7 +149,6 @@ function bnToHex(inputBn) {
 export {
   getPlatform,
   getEnvironmentType,
-  sufficientBalance,
   hexToBn,
   BnMultiplyByFraction,
   checkForError,

app/scripts/lib/util.test.js

@@ -7,7 +7,7 @@ import {
   ENVIRONMENT_TYPE_FULLSCREEN,
   ENVIRONMENT_TYPE_BACKGROUND,
 } from '../../../shared/constants/app';
-import { getEnvironmentType, sufficientBalance } from './util';
+import { getEnvironmentType } from './util';
 
 describe('app utils', function () {
   describe('getEnvironmentType', function () {
@@ -68,44 +68,6 @@ describe('app utils', function () {
     });
   });
 
-  describe('SufficientBalance', function () {
-    it('returns true if max tx cost is equal to balance.', function () {
-      const tx = {
-        value: '0x1',
-        gas: '0x2',
-        gasPrice: '0x3',
-      };
-      const balance = '0x8';
-
-      const result = sufficientBalance(tx, balance);
-      assert.ok(result, 'sufficient balance found.');
-    });
-
-    it('returns true if max tx cost is less than balance.', function () {
-      const tx = {
-        value: '0x1',
-        gas: '0x2',
-        gasPrice: '0x3',
-      };
-      const balance = '0x9';
-
-      const result = sufficientBalance(tx, balance);
-      assert.ok(result, 'sufficient balance found.');
-    });
-
-    it('returns false if max tx cost is more than balance.', function () {
-      const tx = {
-        value: '0x1',
-        gas: '0x2',
-        gasPrice: '0x3',
-      };
-      const balance = '0x6';
-
-      const result = sufficientBalance(tx, balance);
-      assert.ok(!result, 'insufficient balance found.');
-    });
-  });
-
   describe('isPrefixedFormattedHexString', function () {
     it('should return true for valid hex strings', function () {
       assert.equal(