[Fixit-Dec-2012] Auto-launch system-level Chrome post user-level Chrome self-destruction.

chrome/installer/util/util_constants.cc

Index: chrome/installer/util/util_constants.cc
diff --git a/chrome/installer/util/util_constants.cc b/chrome/installer/util/util_constants.cc
index 006c50bc5fe6c992e688a4bb25accd33f27e1bb3..47c3605929bde05ce1befcf943da555c28163002 100644
--- a/chrome/installer/util/util_constants.cc
+++ b/chrome/installer/util/util_constants.cc
@@ -154,6 +154,10 @@ const char kRemoveChromeRegistration[] = "remove-chrome-registration";
 // line flag so that we try the launch only once.
 const char kRunAsAdmin[] = "run-as-admin";
 
+// Combined with --uninstall, signals to setup.exe that this uninstall was
+// triggered by a self-destructing Chrome.
+const char kSelfDestruct[] = "self-destruct";

[grt (UTC plus 2), 2013/01/02 17:59:33]

I think this switch should be a little more explicit since it's for the case of
a self-destruct due to the presence of a system-level install. I can imagine
someday there being a need for Chrome to uninstall itself (i.e., to "self
destruct") for other reasons.

Thinking about this at a high level, we have a choice between using switches
that describe the caller's reason for invoking setup (i.e., "Yo setup! Do the
stuff you need to do to handle a user-level self-destruct because there's a new
Chrome in town!") versus using switches that tell setup specifically what the
caller wants it to do (i.e., "Yo setup! Uninstall yourself without prompting the
user, and don't bother removing anything that might be shared with a
system-level Chrome"). The latter seems to be historically what was used in this
case. What are the pros/cons to sticking with the latter? In this case, the new
switch could be something along the lines of "launch-system-chrome-on-success".

[gab, 2013/01/02 21:15:48]

I can imagine more cases where we would want to do something special in setup on
self-destruct then cases where we would want to fine grain call
--launch-system-chrome-on-success et al.

I think adding a new flag for every nit picky thing we want setup to do because
of the same reason is overkill; I prefer saying "Yo Setup! Please uninstall
Chrome, oh and btw this is because user-level Chrome is self-destructing so do
whatever you need to do in this case as well.".

On the other hand I agree that having a flag that does everything can be
dangerous/hard to maintain, but I don't think this is the case, nor will it be
in the near future...

I don't feel like the actual text value of the flag (i.e. --self-destruct versus
--omg-please-do-tha-thang-you-do-on-self-destruct-cause-hey-man-this-is-it-i-just-self-destructed)
matters at all since it's passed as a code constant on one side and read the
same way on the other (this is not the kind of flag we would mention in any sort
of public API...)

+
 // Install Chrome to system wise location. The default is per user install.
 const char kSystemLevel[] = "system-level";