emacs: also handle paths like "..\chrome/foo/bar" seen in build output

Test case amended to include example.

Review URL: http://codereview.chromium.org/6355015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@72688 0039d316-1c4b-4281-b951-d872f2087c98

tools/emacs/trybot-windows.txt

@@ -55,3 +55,18 @@ browser - 6 error(s), 0 warning(s)
 ---------------------- Done ----------------------
  
     Build: 244 succeeded, 1 failed, 233 up-to-date, 42 skipped
+
+
+We also see weird paths with mixed slashes like this:
+
+--------------------Configuration: inspector_protocol_sources - Debug|Win32----
+--------------------Configuration: installer_util_nacl_win64 - Debug|x64-------
+Compiling...
+google_chrome_distribution_dummy.cc
+helper.cc
+installation_state.cc
+self_reg_work_item.cc
+..\chrome/installer/util/work_item.h(67) : error C2514: 'FilePath' : class has no constructors
+        ..\chrome/installer/util/work_item.h(26) : see declaration of 'FilePath'
+delete_tree_work_item.cc
+delete_reg_key_work_item.cc

tools/emacs/trybot.el

@@ -45,7 +45,15 @@
 
   ; Fix Windows paths ("d:\...\src\").
   (save-excursion
-    (while (re-search-forward "\\(^.:\\\\.*\\\\src\\\\\\)\\(.*?\\)[(:]" nil t)
+    ; This regexp is subtle and rather hard to read. :~(
+    ; Use regexp-builder when making changes to it.
+    (while (re-search-forward
+            (concat
+             ; First part: path leader, either of the form
+             ;   e:\...src\  or  ..\
+             "\\(^.:\\\\.*\\\\src\\\\\\|\\.\\.\\\\\\)"
+             ; Second part: path, followed by error message marker.
+             "\\(.*?\\)[(:]") nil t)
       (replace-match "" nil t nil 1)
       ; Line now looks like:
       ;  foo\bar\baz.cc error message here