fix(state): do not mutate redux state

Using redux-immutable-state-invariant I detected several places where we
were mutating the redux state directly, which should never happen.
Update the code to ensure that we do not mutate the redux state.

Fix #1120

app/reducers/payment.js

@@ -137,8 +137,10 @@ const ACTION_HANDLERS = {
         if (item.paymentRequest !== paymentRequest) {
           return item
         }
-        item.status = 'successful'
-        return item
+        return {
+          ...item,
+          status: 'successful'
+        }
       })
     }
   },
@@ -149,9 +151,11 @@ const ACTION_HANDLERS = {
         if (item.paymentRequest !== paymentRequest) {
           return item
         }
-        item.status = 'failed'
-        item.error = error
-        return item
+        return {
+          ...item,
+          status: 'failed',
+          error
+        }
       })
     }
   },

app/reducers/ticker.js

@@ -134,10 +134,10 @@ tickerSelectors.currencyFilters = createSelector(
     if (!crypto || !network) {
       return []
     }
-    return currencyFilters[crypto].map(item => {
-      item.name = `${network.unitPrefix}${item.name}`
-      return item
-    })
+    return currencyFilters[crypto].map(item => ({
+      ...item,
+      name: `${network.unitPrefix}${item.name}`
+    }))
   }
 )
 

app/reducers/transaction.js

@@ -187,8 +187,10 @@ const ACTION_HANDLERS = {
         if (item.addr !== addr) {
           return item
         }
-        item.status = 'successful'
-        return item
+        return {
+          ...item,
+          status: 'successful'
+        }
       })
     }
   },
@@ -199,9 +201,11 @@ const ACTION_HANDLERS = {
         if (item.addr !== addr) {
           return item
         }
-        item.status = 'failed'
-        item.error = error
-        return item
+        return {
+          ...item,
+          status: 'failed',
+          error
+        }
       })
     }
   },