Made it possible to tell whether an extension is being installed or updated.

chrome/common/extensions/extension.cc

Index: chrome/common/extensions/extension.cc
diff --git a/chrome/common/extensions/extension.cc b/chrome/common/extensions/extension.cc
index c4c1d9a2914762c2dfff9c6ff2a10224d6c1403f..fc9e9b6e6e626409c5b0e3bb4da7e9375cdf4fea 100644
--- a/chrome/common/extensions/extension.cc
+++ b/chrome/common/extensions/extension.cc
@@ -1741,6 +1741,12 @@ ExtensionInfo::ExtensionInfo(const DictionaryValue* manifest,
 
 ExtensionInfo::~ExtensionInfo() {}
 
+InstalledExtensionInfo::InstalledExtensionInfo(
+    const Extension* extension,
+    bool is_update)
+  : extension(extension),

[Devlin, 2013/05/02 06:20:11]

small nit: this and the following lines should have indent of four, i.e.

...
    bool is_update)
    : extension(extension),
...

Please also change the indentation on lines 1753 - 1755.

[Matt Giuca, 2013/05/02 07:17:38]

Done.

+    is_update(is_update) {}
+
 UnloadedExtensionInfo::UnloadedExtensionInfo(
     const Extension* extension,
     extension_misc::UnloadedExtensionReason reason)