Bug 575760: [R-Help] Fix encoding of topic in HTTP url

Change-Id: Ica1a6abf84ae79e24ff16a18db9f7b38eec62bdb
diff --git a/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/rhelp/core/http/RHelpHttpService.java b/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/rhelp/core/http/RHelpHttpService.java
index 4e851d0..6666dbc 100644
--- a/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/rhelp/core/http/RHelpHttpService.java
+++ b/rhelp/org.eclipse.statet.rhelp.core/src/org/eclipse/statet/rhelp/core/http/RHelpHttpService.java
@@ -24,6 +24,7 @@
 import java.net.URI;
 import java.net.URISyntaxException;
 
+import org.eclipse.statet.jcommons.io.UriUtils;
 import org.eclipse.statet.jcommons.lang.NonNullByDefault;
 import org.eclipse.statet.jcommons.lang.Nullable;
 
@@ -177,7 +178,7 @@
 		p.append('/');
 		p.append(LIBRARY_HELP);
 		p.append('/');
-		p.append(topic);
+		p.append(UriUtils.encodePathSegment(topic));
 		return createHttpUrl(p);
 	}