(This is a merge of http://go/wvgerrit/13761 from the Widevine
repository.)
This cleans up our includes to be in Google Style Guide order and in
alphabetic order, for the parts of the code that are expected to
follow Google Style.
This also converts places in our code that were including C headers
in the C++ style (i.e. <cstring> instead of <string.h>) to use C style
instead. This is because, although it was not causing problems for us
yet, on Android these actually include different headers. (<cstring>
is provided by libcxx, while <string.h> is provided by Bionic)
Lastly, this change puts all headers that do not come from within our
project in <brackets> instead of "quotes," which was not being done
consistently.
This change is explicitly NOT trying to standardize the spacing of our
header includes. I have tried to respect, in each file, the spacing
style already present.
Change-Id: If3dc06532ab9b68010285d64518ef21dce3d6354