> Nope. They treat these libraries in the exact same way distributions treat upstream: they include changes which make sense for them and always include README.chromium file, too. It contains detailed explanation of local modifications. Things like Added #ifdef'd definifitions of a few symbols to support 10.5 SDK or Support for Windows (patches/re2-msvc9-chrome.patch). Sometimes these patches are pushed upstream, sometimes they don't pushed anywhere - again, exactly like distributions are doing.
Yes, it's exactly the same as what distros are doing, except for the part where distros *aren't* making incompatible-with-upstream changes to the library and its APIs -- you know, so libiffi.so.5 on fedora is the same as libiffi.so.5 on ubuntu -- Distros attempt to standardize on upstream, while chromium attempts to standardize only within its own sandbox.
This reinvention of privately-bundled-libraries (Aka "self-contained apps") scares the hell out of me, because I remember all too well the security fiascos (eg zlib) that led the distros to ardently unbundle everything and the level of public embarassment it took to get many $bigvendors to update their software.