DMP: Add mmap-partition-alloc

tools/deep_memory_profiler/policy.l2.json

 {
   "components": [
     "second",
     "mmap-profiler",
     "mmap-type-profiler",
     "mmap-tcmalloc",
     "FROM_HERE_FOR_TOTAL",
     "mustbezero",
     "unhooked-absent",
     "unhooked-anonymous",
     "unhooked-file-exec",
     "unhooked-file-nonexec-others",
     "unhooked-file-nonexec-group",
     "unhooked-file-nonexec",
     "unhooked-stack",
     "unhooked-other",
     "no-bucket",
     "mmap-v8-heap-newspace",
     "mmap-v8-heap-coderange",
     "mmap-v8-heap-pagedspace",
     "mmap-v8-other",
     "mmap-gpu-mappedmemorymanager",
     "mmap-gpu-command-ringbuffer",
     "mmap-gpu-transfer-ringbuffer",
     "mmap-gpu-gles2-createbuffer",
     "mmap-skia-font",
+    "mmap-partition-alloc",
     "mmap-catch-all",
     "tc-webcore-cachedmatchedproperties",
     "tc-webcore-fontcache",
     "tc-skia",
     "tc-renderstyle",
     "tc-webcore-sharedbuf",
     "tc-webcore-XHRcreate",
     "tc-webcore-XHRreceived",
     "tc-webcore-docwriter-add",
     "tc-webcore-node-and-doc",
@@ skipping 152 matching lines @@
       "name": "mmap-gpu-gles2-createbuffer",
       "stacktrace": ".*gpu::gles2::BufferTracker::CreateBuffer.*",
       "allocator": "mmap"
     },
     {
       "name": "mmap-skia-font",
       "stacktrace": ".*SkTypeface::openStream.*",
       "allocator": "mmap"
     },
     {
+      "name": "mmap-partition-alloc",
+      "stacktrace": ".*WTF::partitionAllocSlowPath.*",
+      "allocator": "mmap"
+    },
+    {
       "name": "mmap-catch-all",
       "stacktrace": ".*",
       "allocator": "mmap"
     },
     {
       "name": "tc-webcore-cachedmatchedproperties",
       "stacktrace": ".*(WebCore|blink)::CachedMatchedProperties::(set|add).*",
       "allocator": "malloc"
     },
     {
@@ skipping 302 matching lines @@
       "allocator": "optional"
     },
     {
       "name": "other",
       "stacktrace": "optional",
       "allocator": "optional"
     }
   ],
   "version": "POLICY_DEEP_3"
 }