break out of get_pettern only if next line is not a pattern

Author: stasm

fluent/syntax/parser.py

@@ -349,12 +349,14 @@ def get_number(self, ps):
     @with_span
     def get_pattern(self, ps):
         elements = []
-        ps.skip_ws()
+        ps.skip_inline_ws()
 
         while ps.current():
             ch = ps.current()
 
-            if ch == '\n':
+            # The end condition for get_pattern's while loop is a newline
+            # which is not followed by a valid pattern continuation.
+            if ch == '\n' and not ps.is_peek_next_line_pattern():
                 break
 
             if ch == '{':

tests/syntax/fixtures_behavior/multiline_with_placeables.ftl

@@ -0,0 +1,3 @@
+key =
+    Foo { bar }
+    Baz