DevTools: Introduce Memory.getAllTimeSamplingProfile command

It retrieves the currently collected native heap sampling snapshot.
The renderer process had to be started with --sampling-heap-profiler flag to
obtain the snapshot.

BUG=803276

Change-Id: I26ffe5e366abb33245d2f83ffa02bd4350737b7a
Reviewed-on: https://chromium-review.googlesource.com/882290
Commit-Queue: Alexei Filippov <[email protected]>
Reviewed-by: Pavel Feldman <[email protected]>
Cr-Commit-Position: refs/heads/master@{#532233}
diff --git a/third_party/WebKit/LayoutTests/VirtualTestSuites b/third_party/WebKit/LayoutTests/VirtualTestSuites
index 4b4f9139d7..44e93aad 100644
--- a/third_party/WebKit/LayoutTests/VirtualTestSuites
+++ b/third_party/WebKit/LayoutTests/VirtualTestSuites
@@ -653,5 +653,10 @@
     "prefix": "htxg-with-network-service",
     "base": "http/tests/loading/htxg/",
     "args": ["--enable-features=SignedHTTPExchange,NetworkService"]
+  },
+  {
+    "prefix": "sampling-heap-profiler",
+    "base": "inspector-protocol/memory",
+    "args": ["--sampling-heap-profiler"]
   }
 ]