minor #4047 Token - inline $other->getPrototype() to speedup equals()…

… (staabm, keradus)

This PR was merged into the 2.12 branch.

Discussion
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Token - inline $other->getPrototype() to speedup equals()

as measured in #4026 we try to speedup equals() by inlinening the $this->getPrototype() call.

~~also we use FQCN for native functions, because equals() is called a lot.~~

this speedsup the process by 4-5%.

see https://blackfire.io/profiles/compare/f4eefae8-6d09-4ab4-a833-f828d74a7b52/graph
![image](https://user-images.githubusercontent.com/120441/46916011-d6d2c400-cfb4-11e8-89e1-ec64e77477f1.png)

Commits
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1aecb36 Token - inline $other->getPrototype() to speedup equals()

src/Tokenizer/Token.php

@@ -156,7 +156,21 @@ public function clearChanged()
      */
     public function equals($other, $caseSensitive = true)
     {
-        $otherPrototype = $other instanceof self ? $other->getPrototype() : $other;
+        if ($other instanceof self) {
+            // Inlined getPrototype() on this very hot path.
+            // We access the private properties of $other directly to save function call overhead.
+            // This is only possible because $other is of the same class as `self`.
+            if (!$other->isArray) {
+                $otherPrototype = $other->content;
+            } else {
+                $otherPrototype = [
+                    $other->id,
+                    $other->content,
+                ];
+            }
+        } else {
+            $otherPrototype = $other;
+        }
 
         if ($this->isArray !== \is_array($otherPrototype)) {
             return false;