Merge V8 5.3.332.45.  DO NOT MERGE

Test: Manual

FPIIM-449

Change-Id: Id3254828b068abdea3cb10442e0172a8c9a98e03
(cherry picked from commit 13e2dadd00298019ed862f2b2fc5068bba730bcf)
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+Turbolizer is a HTML-based tool that visualizes optimized code along the various
+phases of Turbofan's optimization pipeline, allowing easy navigation between
+source code, Turbofan IR graphs, scheduled IR nodes and generated assembly code.
+
+Turbolizer consumes .json files that are generated per-function by d8 by passing
+the '--trace-turbo' command-line flag.
+
+Host the turbolizer locally by starting a web server that serves the contents of
+the turbolizer directory, e.g.:
+
+cd src/tools/turbolizer
+python -m SimpleHTTPServer 8000
+
+Graph visualization and manipulation based on Mike Bostock's sample code for an
+interactive tool for creating directed graphs. Original source is at
+https://github.com/metacademy/directed-graph-creator and released under the
+MIT/X license.
+
+Icons dervied from the "White Olive Collection" created by Breezi released under
+the Creative Commons BY license.