Merge remote-tracking branch 'ogresCE/MAGETWO-39576-Profiler-JSON' into PR_Branch

app/code/Magento/PageCache/Model/App/FrontController/BuiltinPlugin.php

@@ -76,6 +76,11 @@ class BuiltinPlugin
                 $this->kernel->process($result);
             }
         } else {
+            json_decode($result->getContent());
+            if (json_last_error() == JSON_ERROR_NONE) {
+                // reset profiler to avoid appending profiling stat to JSON response
+                \Magento\Framework\Profiler::reset();
+            }
             $this->addDebugHeader($result, 'X-Magento-Cache-Debug', 'HIT', true);
         }
         return $result;

app/code/Magento/PageCache/Test/Unit/Model/App/FrontController/BuiltinPluginTest.php

@@ -200,6 +200,7 @@ class BuiltinPluginTest extends \PHPUnit_Framework_TestCase
             $this->responseMock->expects($this->never())
                 ->method('setHeader');
         }
+        $this->responseMock->expects($this->once())->method('getContent');
         $this->assertSame(
             $this->responseMock,
             $this->plugin->aroundDispatch($this->frontControllerMock, $this->closure, $this->requestMock)

lib/internal/Magento/Framework/Controller/Result/Json.php

@@ -63,6 +63,8 @@ class Json extends AbstractResult
      */
     protected function render(ResponseInterface $response)
     {
+        // reset profiler to avoid appending profiling stat to JSON response
+        \Magento\Framework\Profiler::reset();
         $this->translateInline->processResponseBody($this->json, true);
         $response->representJson($this->json);
         return $this;