[DevTools] Issue zoom from DevToolsWindow instead of browser commands.

chrome/browser/devtools/devtools_window.cc

Index: chrome/browser/devtools/devtools_window.cc
diff --git a/chrome/browser/devtools/devtools_window.cc b/chrome/browser/devtools/devtools_window.cc
index 6798c1c654d94ec4e5a8fd4d7ceb5b8b8529a9e6..7b20f2e3765346d881ac8c573d4415755139e51b 100644
--- a/chrome/browser/devtools/devtools_window.cc
+++ b/chrome/browser/devtools/devtools_window.cc
@@ -1227,6 +1227,18 @@ void DevToolsWindow::SearchInPath(int request_id,
                                           file_system_path));
 }
 
+void DevToolsWindow::ZoomIn() {
+  chrome_page_zoom::Zoom(web_contents(), content::PAGE_ZOOM_IN);
+}
+
+void DevToolsWindow::ZoomOut() {
+  chrome_page_zoom::Zoom(web_contents(), content::PAGE_ZOOM_OUT);
+}
+
+void DevToolsWindow::ResetZoom() {
+  chrome_page_zoom::Zoom(web_contents(), content::PAGE_ZOOM_RESET);
+}
+
 void DevToolsWindow::FileSavedAs(const std::string& url) {
   base::StringValue url_value(url);
   CallClientFunction("InspectorFrontendAPI.savedURL", &url_value, NULL, NULL);