patch 9.0.0357: 'linebreak' interferes with text property highlight

Problem:    'linebreak' interferes with text property highlight if there is
            syntax highlighting.
Solution:   Check the text prop attributes after combining with syntax
            attributes. (closes #11035)
diff --git a/src/testdir/dumps/Test_prop_linebreak.dump b/src/testdir/dumps/Test_prop_linebreak_1.dump
similarity index 65%
rename from src/testdir/dumps/Test_prop_linebreak.dump
rename to src/testdir/dumps/Test_prop_linebreak_1.dump
index 33be5b3..c1a56e8 100644
--- a/src/testdir/dumps/Test_prop_linebreak.dump
+++ b/src/testdir/dumps/Test_prop_linebreak_1.dump
@@ -1,4 +1,4 @@
->x+0&#ffffff0@49|]+0#ffffff16#e000002| +0#0000000#ffffff0@23
+>x+0&#ffffff0@49|]+0&#40ffff15| +0&#ffffff0@23
 |x@69| @4
 |~+0#4040ff13&| @73
 |~| @73
diff --git a/src/testdir/dumps/Test_prop_linebreak_2.dump b/src/testdir/dumps/Test_prop_linebreak_2.dump
new file mode 100644
index 0000000..e705f71
--- /dev/null
+++ b/src/testdir/dumps/Test_prop_linebreak_2.dump
@@ -0,0 +1,10 @@
+| +0#0000e05#a8a8a8255@1>x+0&#ffffff0@49|]+0&#40ffff15| +0#0000000#ffffff0@21
+| +0#0000e05#a8a8a8255@1|x+0&#ffffff0@69| +0#0000000&@2
+|~+0#4040ff13&| @73
+|~| @73
+|~| @73
+|~| @73
+|~| @73
+|~| @73
+|~| @73
+| +0#0000000&@56|1|,|1| @10|A|l@1| 
diff --git a/src/testdir/test_textprop.vim b/src/testdir/test_textprop.vim
index 03ae9c9..21d751f 100644
--- a/src/testdir/test_textprop.vim
+++ b/src/testdir/test_textprop.vim
@@ -1925,12 +1925,21 @@
   let lines =<< trim END
     set breakindent linebreak breakat+=]
     call printf('%s]%s', repeat('x', 50), repeat('x', 70))->setline(1)
-    call prop_type_add('test', #{highlight: 'ErrorMsg'})
+    call prop_type_add('test', #{highlight: 'MatchParen'})
     call prop_add(1, 51, #{length: 1, type: 'test'})
+    func AddMatch()
+      syntax on
+      syntax match xTest /.*/
+      hi link xTest Comment
+      set signcolumn=yes
+    endfunc
   END
   call writefile(lines, 'XscriptPropLinebreak')
   let buf = RunVimInTerminal('-S XscriptPropLinebreak', #{rows: 10})
-  call VerifyScreenDump(buf, 'Test_prop_linebreak', {})
+  call VerifyScreenDump(buf, 'Test_prop_linebreak_1', {})
+
+  call term_sendkeys(buf, ":call AddMatch()\<CR>")
+  call VerifyScreenDump(buf, 'Test_prop_linebreak_2', {})
 
   call StopVimInTerminal(buf)
   call delete('XscriptPropLinebreak')