Remove shield for Conduit API responses

Summary: 'cuz we don't need it and it's lame complexity for API clients of all kinds. Rip the band-aid off now.

Test Plan: used conduit console and verified no more shield. also did some JS stuff around the suite to verify I didn't kill JS

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T891

Differential Revision: https://secure.phabricator.com/D3265

src/aphront/response/AphrontJSONResponse.php

@@ -22,15 +22,31 @@
 final class AphrontJSONResponse extends AphrontResponse {
 
   private $content;
+  private $addJSONShield;
 
   public function setContent($content) {
     $this->content = $content;
     return $this;
   }
 
+  public function setAddJSONShield($should_add) {
+    $this->addJSONShield = $should_add;
+    return $this;
+  }
+
+  public function shouldAddJSONShield() {
+    if ($this->addJSONShield === null) {
+      return true;
+    }
+    return (bool) $this->addJSONShield;
+  }
+
   public function buildResponseString() {
     $response = $this->encodeJSONForHTTPResponse($this->content);
-    return $this->addJSONShield($response, $use_javelin_shield = false);
+    if ($this->shouldAddJSONShield()) {
+      $response = $this->addJSONShield($response, $use_javelin_shield = false);
+    }
+    return $response;
   }
 
   public function getHeaders() {
@@ -40,5 +56,4 @@ final class AphrontJSONResponse extends AphrontResponse {
     $headers = array_merge(parent::getHeaders(), $headers);
     return $headers;
   }
-
 }