minor #3275 Identity Equals - Best practices (hectorprats)

This PR was submitted for the 3.x branch but it was merged into the 1.x branch instead.

Discussion
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Identity Equals - Best practices

all the equals are with identity equals, except these.

It's better normalize all the comparatives operations.

Commits
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60d5b4bc Identity Equals - Best practices

src/Extension/CoreExtension.php

@@ -539,11 +539,11 @@ function twig_replace_filter($str, $from, $to = null)
  */
 function twig_round($value, $precision = 0, $method = 'common')
 {
-    if ('common' == $method) {
+    if ('common' === $method) {
         return round($value, $precision);
     }
 
-    if ('ceil' != $method && 'floor' != $method) {
+    if ('ceil' !== $method && 'floor' !== $method) {
         throw new RuntimeError('The round filter only supports the "common", "ceil", and "floor" methods.');
     }
 
@@ -1504,7 +1504,7 @@ function twig_to_array($seq, $preserveKeys = true)
 function twig_test_empty($value)
 {
     if ($value instanceof \Countable) {
-        return 0 == \count($value);
+        return 0 === \count($value);
     }
 
     if ($value instanceof \Traversable) {