Update Crashpad to 1f28a123a4c9449e3d7ddad4ff00dacd366d5216

third_party/crashpad/crashpad/doc/overview_design.md

Index: third_party/crashpad/crashpad/doc/overview_design.md
diff --git a/third_party/crashpad/crashpad/doc/overview_design.md b/third_party/crashpad/crashpad/doc/overview_design.md
index ad871c18b7c571d2c68d049d4cda4beb508bda58..07a7d65111a51b4229e0f48e16e8aaf5279d509f 100644
--- a/third_party/crashpad/crashpad/doc/overview_design.md
+++ b/third_party/crashpad/crashpad/doc/overview_design.md
@@ -452,6 +452,8 @@ suspend and resume and such.
 
 ### Extensibility
 
+#### Client Extensibility
+
 Clients are able to extend the generated crash reports in two ways, by
 manipulating their CrashpadInfo structure.
 The two extensibility points are:
@@ -461,6 +463,18 @@ The two extensibility points are:
 In both cases the CrashpadInfo structure has to be updated before a crash
 occurs.
 
+##### Embedder Extensibility
+
+Additionally, embedders of the handler can provide "user stream data source"
+instances to the handler's main function. Any time a minidump is written, these
+instances get called.
+
+Each data source may contribute a custom stream to the minidump, which can be
+computed from e.g. system or application state relevant to the crash.
+
+As a case in point, it can be handy to know whether the system was under memory
+or other resource duress at the time of crash.
+
 ### Dependencies
 
 Aside from system headers and APIs, when used outside of Chromium, Crashpad has