clang-format: [JS] do not wrap after async/await.

[mprobst]

Summary

Otherwise automatic semicolon insertion can trigger, i.e. wrapping
produces invalid syntax.

[djasper]

Looks good.

cfe/trunk/lib/Format/TokenAnnotator.cpp

if (Left.isOneOf(Keywords.kw_throws, Keywords.kw_extends,
                      Keywords.kw_implements))
       return false;
     if (Right.isOneOf(Keywords.kw_throws, Keywords.kw_extends,
                       Keywords.kw_implements))
       return true;
   } else if (Style.Language == FormatStyle::LK_JavaScript) {
     const FormatToken *NonComment = Right.getPreviousNonComment();
     if (NonComment &&
-        NonComment->isOneOf(tok::kw_return, Keywords.kw_yield, tok::kw_continue,
-                            tok::kw_break, tok::kw_throw, Keywords.kw_interface,
-                            Keywords.kw_type, tok::kw_static, tok::kw_public,
-                            tok::kw_private, tok::kw_protected,
-                            Keywords.kw_readonly, Keywords.kw_abstract,
-                            Keywords.kw_get, Keywords.kw_set))
+        NonComment->isOneOf(
+            tok::kw_return, Keywords.kw_yield, tok::kw_continue, tok::kw_break,
+            tok::kw_throw, Keywords.kw_interface, Keywords.kw_type,
+            tok::kw_static, tok::kw_public, tok::kw_private, tok::kw_protected,
+            Keywords.kw_readonly, Keywords.kw_abstract, Keywords.kw_get,
+            Keywords.kw_set, Keywords.kw_async, Keywords.kw_await))
       return false; // Otherwise automatic semicolon insertion would trigger.
     if (Left.Tok.getIdentifierInfo() &&
         Right.startsSequence(tok::l_square, tok::r_square))
       return false;  // breaking in "foo[]" creates illegal TS type syntax.
     if (Left.is(TT_JsFatArrow) && Right.is(tok::l_brace))
       return false;
     if (Left.is(TT_JsTypeColon))
       return true;

cfe/trunk/unittests/Format/FormatTestJS.cpp

verifyFormat("class X {\n"
                "class X {\n"
                "  readonly ratherLongField = 1;\n"
                "}",
                getGoogleJSStyleWithColumns(20));
   verifyFormat("const x = (5 + 9)\n"
                "const y = 3\n",
                "const x = (   5 +    9)\n"
                "const y = 3\n");
+  // Ideally the foo() bit should be indented relative to the async function().
+  verifyFormat("async function\n"
+               "foo() {}",
+               getGoogleJSStyleWithColumns(10));
+  verifyFormat("await theReckoning;", getGoogleJSStyleWithColumns(10));
 }
 
 TEST_F(FormatTestJS, AutomaticSemicolonInsertionHeuristic) {
   verifyFormat("a\n"
                "b;",
                " a \n"
                " b ;");
   verifyFormat("a()\n"