Roll inspector_protocol to 8515c2a1c5c016646b61221586cd4e5839f425ee

This roll includes:
8515c2a1c UBSan fix
9977c471b (does not touch files imported into V8)
9cba74155 (does not touch files imported into V8)

Bug: v8:3770
Change-Id: If5ae5e7c6a7a81a246c8376545c4437cacaf1dc3
Reviewed-on: https://chromium-review.googlesource.com/c/1436230Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59103}

third_party/inspector_protocol/README.v8

@@ -2,7 +2,7 @@ Name: inspector protocol
 Short Name: inspector_protocol
 URL: https://chromium.googlesource.com/deps/inspector_protocol/
 Version: 0
-Revision: fdbdb154336fc1f15a0a6775349dd90243b8d3fc
+Revision: 8515c2a1c5c016646b61221586cd4e5839f425ee
 License: BSD
 License File: LICENSE
 Security Critical: no

third_party/inspector_protocol/lib/Maybe_h.template

@@ -83,7 +83,7 @@ protected:
 template<>
 class Maybe<bool> : public MaybeBase<bool> {
 public:
-    Maybe() { }
+    Maybe() { m_value = false; }
     Maybe(bool value) : MaybeBase(value) { }
     Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
     using MaybeBase::operator=;
@@ -92,7 +92,7 @@ public:
 template<>
 class Maybe<int> : public MaybeBase<int> {
 public:
-    Maybe() { }
+    Maybe() { m_value = 0; }
     Maybe(int value) : MaybeBase(value) { }
     Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
     using MaybeBase::operator=;
@@ -101,7 +101,7 @@ public:
 template<>
 class Maybe<double> : public MaybeBase<double> {
 public:
-    Maybe() { }
+    Maybe() { m_value = 0; }
     Maybe(double value) : MaybeBase(value) { }
     Maybe(Maybe&& other) IP_NOEXCEPT : MaybeBase(std::move(other)) {}
     using MaybeBase::operator=;