Make EnvironmentVariables::appendValue() handle the case where the ex…

…isting value is an empty string.

https://bugs.webkit.org/show_bug.cgi?id=141818.

Patch by Remy Demarest <rdemarest@apple.com> on 2015-02-19
Reviewed by Dan Bernstein.

* UIProcess/Launcher/mac/EnvironmentVariables.cpp:
(WebKit::EnvironmentVariables::appendValue): If the existing value is an empty string, replace it rather than
append to it.

Canonical link: https://commits.webkit.org/159845@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@180379 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebKit2/ChangeLog

@@ -1,3 +1,14 @@
+2015-02-19  Remy Demarest  <rdemarest@apple.com>
+
+        Make EnvironmentVariables::appendValue() handle the case where the existing value is an empty string.
+        https://bugs.webkit.org/show_bug.cgi?id=141818.
+
+        Reviewed by Dan Bernstein.
+
+        * UIProcess/Launcher/mac/EnvironmentVariables.cpp:
+        (WebKit::EnvironmentVariables::appendValue): If the existing value is an empty string, replace it rather than
+        append to it.
+
 2015-02-19  Anders Carlsson  <andersca@apple.com>
 
         Make C SPI objects and modern API objects toll-free bridged

Source/WebKit2/UIProcess/Launcher/mac/EnvironmentVariables.cpp

@@ -79,7 +79,7 @@ const char* EnvironmentVariables::get(const char* name) const
 void EnvironmentVariables::appendValue(const char* name, const char* value, char separator)
 {
     const char* existingValue = get(name);
-    if (!existingValue) {
+    if (!existingValue || !strlen(existingValue)) {
         set(name, value);
         return;
     }