Specify the WebAPK server URL in Chromium source code

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index 19fc161da154168457c504230d5fe9d46a13af99..939285effe066a5ddd72060b13905bb89b4ba93d 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1062,6 +1062,9 @@ const char kTabManagementExperimentTypeDisabled[] =
     "tab-management-experiment-type-disabled";
 const char kTabManagementExperimentTypeElderberry[] =
     "tab-management-experiment-type-elderberry";
+
+// Custom WebAPK server URL for the sake of testing.
+const char kWebApkServerUrl[] = "webapk-server-url";
 #endif  // defined(OS_ANDROID)
 
 #if defined(OS_CHROMEOS)