DevTools: [HeapTracking] keep same total time for the recording snapshot and for its recorded version.
DevTools: [HeapTracking] keep same total time for the recording snapshot and for its recorded version.

User might be confused by the changing scale of the live objects graph when he pressed stop record button.
We can archive that by persisting totalTime property in profileSamples object.

BUG=none
TEST=none
R=alph@chromium.org, yurys@chromium.org

Review URL: https://codereview.chromium.org/15250008

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@150889 bbb929c8-8fbe-4397-9dbb-9b2b20218538

PeterWangIntel/blink-crosswalk,XiaosongWei/blink-crosswalk,crosswalk-project/blink-crosswalk-efl,Pluto-tv/blink-crosswalk,crosswalk-project/blink-crosswalk-efl,jtg-gg/blink,crosswalk-project/blink-crosswalk-efl,ondra-novak/blink,jtg-gg/blink,Pluto-tv/blink-crosswalk,Bysmyyr/blink-crosswalk,PeterWangIntel/blink-crosswalk,Bysmyyr/blink-crosswalk,hgl888/blink-crosswalk-efl,hgl888/blink-crosswalk-efl,kurli/blink-crosswalk,smishenk/blink-crosswalk,nwjs/blink,Bysmyyr/blink-crosswalk,hgl888/blink-crosswalk-efl,modulexcite/blink,modulexcite/blink,Pluto-tv/blink-crosswalk,crosswalk-project/blink-crosswalk-efl,PeterWangIntel/blink-crosswalk,crosswalk-project/blink-crosswalk-efl,smishenk/blink-crosswalk,XiaosongWei/blink-crosswalk,ondra-novak/blink,hgl888/blink-crosswalk-efl,Bysmyyr/blink-crosswalk,Bysmyyr/blink-crosswalk,PeterWangIntel/blink-crosswalk,nwjs/blink,Bysmyyr/blink-crosswalk,nwjs/blink,XiaosongWei/blink-crosswalk,Bysmyyr/blink-crosswalk,nwjs/blink,modulexcite/blink,ondra-novak/blink,modulexcite/blink,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,hgl888/blink-crosswalk-efl,jtg-gg/blink,jtg-gg/blink,ondra-novak/blink,jtg-gg/blink,Bysmyyr/blink-crosswalk,ondra-novak/blink,jtg-gg/blink,smishenk/blink-crosswalk,crosswalk-project/blink-crosswalk-efl,PeterWangIntel/blink-crosswalk,nwjs/blink,ondra-novak/blink,jtg-gg/blink,modulexcite/blink,ondra-novak/blink,XiaosongWei/blink-crosswalk,PeterWangIntel/blink-crosswalk,jtg-gg/blink,hgl888/blink-crosswalk-efl,hgl888/blink-crosswalk-efl,PeterWangIntel/blink-crosswalk,jtg-gg/blink,nwjs/blink,XiaosongWei/blink-crosswalk,Pluto-tv/blink-crosswalk,smishenk/blink-crosswalk,modulexcite/blink,XiaosongWei/blink-crosswalk,smishenk/blink-crosswalk,crosswalk-project/blink-crosswalk-efl,kurli/blink-crosswalk,kurli/blink-crosswalk,Pluto-tv/blink-crosswalk,hgl888/blink-crosswalk-efl,XiaosongWei/blink-crosswalk,XiaosongWei/blink-crosswalk,ondra-novak/blink,kurli/blink-crosswalk,modulexcite/blink,hgl888/blink-crosswalk-efl,crosswalk-project/blink-crosswalk-efl,XiaosongWei/blink-crosswalk,smishenk/blink-crosswalk,PeterWangIntel/blink-crosswalk,ondra-novak/blink,smishenk/blink-crosswalk,kurli/blink-crosswalk,Pluto-tv/blink-crosswalk,nwjs/blink,Bysmyyr/blink-crosswalk,Bysmyyr/blink-crosswalk,nwjs/blink,hgl888/blink-crosswalk-efl,kurli/blink-crosswalk,PeterWangIntel/blink-crosswalk,kurli/blink-crosswalk,Pluto-tv/blink-crosswalk,smishenk/blink-crosswalk,crosswalk-project/blink-crosswalk-efl,jtg-gg/blink,XiaosongWei/blink-crosswalk,modulexcite/blink,modulexcite/blink,Pluto-tv/blink-crosswalk,smishenk/blink-crosswalk,kurli/blink-crosswalk,kurli/blink-crosswalk,nwjs/blink,PeterWangIntel/blink-crosswalk,kurli/blink-crosswalk,smishenk/blink-crosswalk,nwjs/blink,modulexcite/blink