<rdar://problem/13069948>

Major fixed to allow reading files that are over 4GB. The main problems were that the DataExtractor was using 32 bit offsets as a data cursor, and since we mmap all of our object files we could run into cases where if we had a very large core file that was over 4GB, we were running into the 4GB boundary.

So I defined a new "lldb::offset_t" which should be used for all file offsets.

After making this change, I enabled warnings for data loss and for enexpected implicit conversions temporarily and found a ton of things that I fixed.

Any functions that take an index internally, should use "size_t" for any indexes and also should return "size_t" for any sizes of collections.

llvm-svn: 173463
diff --git a/lldb/source/Core/StreamString.cpp b/lldb/source/Core/StreamString.cpp
index 1c6f146..8d7d039 100644
--- a/lldb/source/Core/StreamString.cpp
+++ b/lldb/source/Core/StreamString.cpp
@@ -34,7 +34,7 @@
     // Nothing to do when flushing a buffer based stream...
 }
 
-int
+size_t
 StreamString::Write (const void *s, size_t length)
 {
     m_packet.append ((char *)s, length);