Merge branch 'approvals-bug' into 'master'

Force JSON parsing of approvals API response data.

Closes #1575

See merge request !1095

app/assets/javascripts/merge_request_widget/approvals/approvals_store.js.es6

@@ -36,19 +36,19 @@
 
     fetch() {
       return this.api.fetchApprovals()
-        .then(res => this.assignToRootStore('approvals', res.data))
+        .then(res => this.assignToRootStore('approvals', res.json()))
         .then(data => this.setMergeRequestAcceptanceStatus(data.approvals_left));
     }
 
     approve() {
       return this.api.approveMergeRequest()
-        .then(res => this.assignToRootStore('approvals', res.data))
+        .then(res => this.assignToRootStore('approvals', res.json()))
         .then(data => this.setMergeRequestAcceptanceStatus(data.approvals_left));
     }
 
     unapprove() {
       return this.api.unapproveMergeRequest()
-        .then(res => this.assignToRootStore('approvals', res.data))
+        .then(res => this.assignToRootStore('approvals', res.json()))
         .then(data => this.setMergeRequestAcceptanceStatus(data.approvals_left));
     }