patch 9.0.0779: lsl and lm3 file extensions are not recognized

Problem:    lsl and lm3 file extensions are not recognized.
Solution:   Add *.lsl and *.lm3 patterns. (Doug Kearns, closes #11384)

src/testdir/test_filetype.vim

@@ -365,7 +365,7 @@ let s:filename_checks = {
     \ 'mmp': ['file.mmp'],
     \ 'modconf': ['/etc/modules.conf', '/etc/modules', '/etc/conf.modules', '/etc/modprobe.file', 'any/etc/conf.modules', 'any/etc/modprobe.file', 'any/etc/modules', 'any/etc/modules.conf'],
     \ 'modula2': ['file.m2', 'file.mi'],
-    \ 'modula3': ['file.m3', 'file.mg', 'file.i3', 'file.ig'],
+    \ 'modula3': ['file.m3', 'file.mg', 'file.i3', 'file.ig', 'file.lm3'],
     \ 'monk': ['file.isc', 'file.monk', 'file.ssc', 'file.tsc'],
     \ 'moo': ['file.moo'],
     \ 'moonscript': ['file.moon'],
@@ -1931,4 +1931,35 @@ func Test_inc_file()
   filetype off
 endfunc
 
+func Test_lsl_file()
+  filetype on
+
+  call writefile(['looks like Linden Scripting Language'], 'Xfile.lsl', 'D')
+  split Xfile.lsl
+  call assert_equal('lsl', &filetype)
+  bwipe!
+
+  " Test dist#ft#FTlsl()
+
+  let g:filetype_lsl = 'larch'
+  split Xfile.lsl
+  call assert_equal('larch', &filetype)
+  bwipe!
+  unlet g:filetype_lsl
+
+  " Larch Shared Language
+
+  call writefile(['% larch comment'], 'Xfile.lsl')
+  split Xfile.lsl
+  call assert_equal('larch', &filetype)
+  bwipe!
+
+  call writefile(['foo: trait'], 'Xfile.lsl')
+  split Xfile.lsl
+  call assert_equal('larch', &filetype)
+  bwipe!
+
+  filetype off
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    779,
 /**/
     778,
 /**/