Add chrome.webstore API methods to allow sites to see progress of installation

chrome/browser/extensions/install_observer.h

Index: chrome/browser/extensions/install_observer.h
diff --git a/chrome/browser/extensions/install_observer.h b/chrome/browser/extensions/install_observer.h
index 6c64cca7e815e66eef55ca3c09ae1f6b92f37e1d..6f3097743825f8bee53bc9caaa32659b01803922 100644
--- a/chrome/browser/extensions/install_observer.h
+++ b/chrome/browser/extensions/install_observer.h
@@ -35,6 +35,12 @@ class InstallObserver {
   // is called before the extension download begins.
   virtual void OnBeginExtensionInstall(const ExtensionInstallParams& params);
 
+  // Called when the Extension begins the download process.
+  // This is typically, but not always, almost immediately after
+  // OnBeginExtensionInstall(). In some cases, though, the extension may already
+  // be downloaded, so we don't want to group the two together incorrectly.

[not at google - send to devlin, 2014/02/27 21:49:56]

nit: this comment has too many commas in it.

[Devlin, 2014/02/28 18:04:51]

Haha fair enough, I suppose, though, really, there could have been, maybe, a few
more?

+  virtual void OnBeginExtensionDownload(const std::string& extension_id);
+
   // Called whenever the extension download is updated.
   // Note: Some extensions have multiple modules, so the percent included here
   // is a simple calculation of:
@@ -42,6 +48,10 @@ class InstallObserver {
   virtual void OnDownloadProgress(const std::string& extension_id,
                                   int percent_downloaded);
 
+  // Called when the necessary downloads have completed, and the crx

[not at google - send to devlin, 2014/02/27 21:49:56]

nit: unnecessary comma

[Devlin, 2014/02/28 18:04:51]

I'm defending this one! :P
http://www.hamilton.edu/writing/seven-sins-of-writing/the-second-deadly-sin-i...
Rule (a).

+  // installation is due to start.
+  virtual void OnBeginCrxInstall(const std::string& extension_id);
+
   // Called if the extension fails to install.
   virtual void OnInstallFailure(const std::string& extension_id);