gh-135953: Add flamegraph reporter to sampling profiler

.gitattributes

@@ -103,3 +103,4 @@ Python/stdlib_module_names.h                        generated
 Tools/peg_generator/pegen/grammar_parser.py         generated
 aclocal.m4                                          generated
 configure                                           generated
+*.min.js                                            generated

Doc/license.rst

@@ -1169,3 +1169,33 @@ contributors. The pyzstd code is distributed under the 3-Clause BSD License::
   CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+Profiling module
+----------------
+
+The :mod:`!profiling` module includes vendored third-party libraries in
+:file:`Lib/profiling/sampling/_vendor/` with the following licenses:
+
+**d3-flamegraph**
+
+The d3-flamegraph library is distributed under the Apache License, Version 2.0.
+See the OpenSSL section above for the full text of the Apache License Version 2.0.
+
+**d3.js**
+
+The d3.js library contains the following notice::
+
+  Copyright 2010-2021 Mike Bostock
+
+  Permission to use, copy, modify, and/or distribute this software for any purpose
+  with or without fee is hereby granted, provided that the above copyright notice
+  and this permission notice appear in all copies.
+
+  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+  REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+  INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+  OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+  TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
+  THIS SOFTWARE.

Lib/profiling/sampling/_vendor/d3-flame-graph/4.1.3/d3-flamegraph.css

@@ -0,0 +1,46 @@
+.d3-flame-graph rect {
+  stroke: #EEEEEE;
+  fill-opacity: .8;
+}
+
+.d3-flame-graph rect:hover {
+  stroke: #474747;
+  stroke-width: 0.5;
+  cursor: pointer;
+}
+
+.d3-flame-graph-label {
+  pointer-events: none;
+  white-space: nowrap;
+  text-overflow: ellipsis;
+  overflow: hidden;
+  font-size: 12px;
+  font-family: Verdana;
+  margin-left: 4px;
+  margin-right: 4px;
+  line-height: 1.5;
+  padding: 0 0 0;
+  font-weight: 400;
+  color: black;
+  text-align: left;
+}
+
+.d3-flame-graph .fade {
+  opacity: 0.6 !important;
+}
+
+.d3-flame-graph .title {
+  font-size: 20px;
+  font-family: Verdana;
+}
+
+.d3-flame-graph-tip {
+    background-color: black;
+    border: none;
+    border-radius: 3px;
+    padding: 5px 10px 5px 10px;
+    min-width: 250px;
+    text-align: left;
+    color: white;
+    z-index: 10;
+}