Bug 1103216: update Google parameters, r=gavin, f=mfinkle, test changes r=felipe

--HG--
extra : transplant_source : %12%07%00%00%E1kA%0E%0B%24%0A%89%94%9C%17%B5EE%1E%B9
Bug 1104925: update Yahoo search plugin for en-US, r=gavin/mconnor

--HG--
extra : transplant_source : %FE%08%0D%0Er%13%2B%D4%1Fv%3C%CC%9A%F9%A6%FBK%A4%AE%22
Bug 1102416: make Yahoo the default search plugin for en-US in American time zones, r=dolske, a=me