Don't split T_INLINE_HTML at partial PHP tag

If <?php occurs without required trailing whitespace, we should keep
it as part of a single T_INLINE_HTML region.

Zend/zend_language_scanner.l

@@ -2059,8 +2059,12 @@ inline_char_handler:
 		}
 
 		if (*YYCURSOR == '?') {
-			if (CG(short_tags) || !strncasecmp((char*)YYCURSOR + 1, "php", 3) || (*(YYCURSOR + 1) == '=')) { /* Assume [ \t\n\r] follows "php" */
-
+			if (CG(short_tags) /* <? */
+				|| (*(YYCURSOR + 1) == '=') /* <?= */
+				|| (!strncasecmp((char*)YYCURSOR + 1, "php", 3) && /* <?php[ \t\r\n] */
+					(YYCURSOR[4] == ' ' || YYCURSOR[4] == '\t' ||
+					YYCURSOR[4] == '\n' || YYCURSOR[4] == '\r'))
+			) {
 				YYCURSOR--;
 				break;
 			}

ext/tokenizer/no_inline_html_split.phpt

@@ -0,0 +1,24 @@
+--TEST--
+Inline HTML should not be split at partial PHP tags
+--INI--
+short_open_tag=0
+--FILE--
+<?php
+
+var_dump(token_get_all(<<<'PHP'
+Foo<?phpBar
+PHP));
+
+?>
+--EXPECTF--
+array(1) {
+  [0]=>
+  array(3) {
+    [0]=>
+    int(%d)
+    [1]=>
+    string(11) "Foo<?phpBar"
+    [2]=>
+    int(1)
+  }
+}