[JavaScript] Fix ST freezing (#4003)

Fixes sublimehq/sublime_text#6416

Regressed by #3836

This commit refactors for loop conditions to prevent ST's syntax engine to run
into an infinite loop, if multiple nested for loops appear within branches,
such as arrow functions.

The issue seems to be triggered by

```yml
  for-condition-contents:
    - match: ''
      branch_point: for-in-of
      branch:
        - for-in-of
        - for-oldstyle
      pop: 1
```

in conjunction with newlines.

Note: It somewhat reorganizes expressions contexts a little bit.

JavaScript/JavaScript.sublime-syntax

@@ -842,31 +842,25 @@ contexts:
     - include: else-pop
 
   for-condition:
-    - match: '\('
-      scope: punctuation.section.group.begin.js
-      set:
-        - for-condition-end
-        - for-condition-contents
+    - match: \(
+      scope: meta.group.js punctuation.section.group.begin.js
+      branch_point: for-in-of
+      branch:
+        - for-in-of
+        - for-oldstyle
     - include: else-pop
 
   for-condition-end:
     - meta_scope: meta.group.js
-
-    - match: '\)'
+    - match: \)
       scope: punctuation.section.group.end.js
       pop: 1
 
-  for-condition-contents:
-    - match: ''
-      branch_point: for-in-of
-      branch:
-        - for-in-of
-        - for-oldstyle
-      pop: 1
-
   for-in-of:
+    - meta_include_prototype: false
     - match: ''
       set:
+        - for-condition-end
         - expression
         - for-in-of-word
         - for-in-of-declaration
@@ -916,6 +910,7 @@ contexts:
       fail: for-in-of
 
   for-oldstyle:
+    - meta_include_prototype: false
     - match: ''
       set:
         - for-oldstyle-rest
@@ -927,16 +922,14 @@ contexts:
       set:
         - variable-binding-list-top
         - variable-binding-top
-    - match: (?=\S)
-      set: expression
+    - include: else-pop
 
   for-oldstyle-rest:
-    - match: (?=\))
-      pop: 1
+    - meta_scope: meta.group.js
     - match: ;
       scope: punctuation.separator.expression.js
-    - match: (?=\S)
-      push: expression
+    - include: for-condition-end
+    - include: expressions
 
   block-scope:
     - include: block
@@ -1055,25 +1048,32 @@ contexts:
     - include: parenthesized-expression
     - include: expression-begin
 
-  expression-break:
-    - match: (?=[;})\]])
-      pop: 1
+  expressions:
+    - match: (?=\S)
+      push: [ expression-end, expression-begin ]
 
   expression:
     - meta_include_prototype: false
     - match: ''
       set: [ expression-end, expression-begin ]
 
+  expression-list:
+    - include: expression-break
+    - include: comma-separator
+    - include: expressions-no-comma
+
+  expressions-no-comma:
+    - match: (?=\S)
+      push: [ expression-end-no-comma, expression-begin ]
+
   expression-no-comma:
     - meta_include_prototype: false
     - match: ''
       set: [ expression-end-no-comma, expression-begin ]
 
-  expression-list:
-    - include: expression-break
-    - include: comma-separator
-    - match: (?=\S)
-      push: expression-no-comma
+  expression-break:
+    - match: (?=[;})\]])
+      pop: 1
 
   left-expression-end:
     - include: expression-break