Move base to DEPS

base/allocator/README

-Notes about the Chrome memory allocator.
-
-Background
-----------
-We use this library as a generic way to fork into any of several allocators.
-Currently we can, at runtime, switch between:
-   the default windows allocator
-   the windows low-fragmentation-heap
-   tcmalloc
-   jemalloc (the heap used most notably within Mozilla Firefox)
-
-The mechanism for hooking LIBCMT in windows is rather tricky.  The core
-problem is that by default, the windows library does not declare malloc and
-free as weak symbols.  Because of this, they cannot be overriden.  To work
-around this, we start with the LIBCMT.LIB, and manually remove all allocator
-related functions from it using the visual studio library tool.  Once removed,
-we can now link against the library and provide custom versions of the 
-allocator related functionality.
-
-
-Source code
------------
-This directory contains just the allocator (i.e. shim) layer that switches
-between the different underlying memory allocation implementations.
-
-The tcmalloc and jemalloc libraries originate outside of Chromium
-and exist in ../../third_party/tcmalloc and ../../third_party/jemalloc
-(currently, the actual locations are defined in the allocator.gyp file).
-The third party sources use a vendor-branch SCM pattern to track
-Chromium-specific changes independently from upstream changes.
-
-The general intent is to push local changes upstream so that over
-time we no longer need any forked files.
-
-
-Adding a new allocator
-----------------------
-Adding a new allocator requires definition of the following five functions:
-
-  extern "C" {
-    bool init();
-    void* malloc(size_t s);
-    void* realloc(void* p, size_t s);
-    void free(void* s);
-    size_t msize(void* p);
-  }
-
-All other allocation related functions (new/delete/calloc/etc) have been
-implemented generically to work across all allocators.
-
-
-Usage
------
-You can use the different allocators by setting the environment variable
-CHROME_ALLOCATOR to:
-   "tcmalloc"  - TC Malloc (default)
-   "jemalloc"  - JE Malloc
-   "winheap"   - Windows default heap
-   "winlfh"    - Windows Low-Fragmentation heap