Fix issue with rendering elements inside blocks.

Fixes exceptions being raised when you tried to render
elements inside blocks.  Instead compare the number of open blocks.
This should not change before/after rendering a view.

lib/Cake/View/View.php

@@ -827,12 +827,10 @@ protected function _render($viewFile, $data = array()) {
 			$data = $this->viewVars;
 		}
 		$this->_current = $viewFile;
+		$initialBlocks = count($this->Blocks->unclosed());
 
 		$this->getEventManager()->dispatch(new CakeEvent('View.beforeRenderFile', $this, array($viewFile)));
 		$content = $this->_evaluate($viewFile, $data);
-		if ($this->Blocks->active()) {
-			throw new CakeException(__d('cake_dev', 'The "%s" block was left open.', $this->Blocks->active()));
-		}
 		$afterEvent = new CakeEvent('View.afterRenderFile', $this, array($viewFile, $content));
 		//TODO: For BC puporses, set extra info in the event object. Remove when appropriate
 		$afterEvent->modParams = 1;
@@ -843,11 +841,16 @@ protected function _render($viewFile, $data = array()) {
 			$this->_stack[] = $this->fetch('content');
 			$this->assign('content', $content);
 
-			$content = $this->_render($this->_parents[$viewFile], $data);
-
+			$content = $this->_render($this->_parents[$viewFile]);
 			$this->assign('content', array_pop($this->_stack));
 		}
 
+		$remainingBlocks = count($this->Blocks->unclosed());
+
+		if ($initialBlocks !== $remainingBlocks) {
+			throw new CakeException(__d('cake_dev', 'The "%s" block was left open. Blocks are not allowed to cross files.', $this->Blocks->active()));
+		}
+
 		return $content;
 	}
 

lib/Cake/View/ViewBlock.php

@@ -145,4 +145,13 @@ public function keys() {
 	public function active() {
 		return end($this->_active);
 	}
+
+/**
+ * Get the names of the unclosed/active blocks.
+ *
+ * @return array An array of unclosed blocks.
+ */
+	public function unclosed() {
+		return $this->_active;
+	}
 }