win: Add and use a custom CaptureContext() implementation

snapshot/win/exception_snapshot_win_test.cc

Index: snapshot/win/exception_snapshot_win_test.cc
diff --git a/snapshot/win/exception_snapshot_win_test.cc b/snapshot/win/exception_snapshot_win_test.cc
index 4108a575978f92dc10f2b325b64fb0a078aef71b..3fc8c6d16fd2a23d5a312bd74f2ef8fa8bfa32bf 100644
--- a/snapshot/win/exception_snapshot_win_test.cc
+++ b/snapshot/win/exception_snapshot_win_test.cc
@@ -192,8 +192,7 @@ class SimulateDelegate : public ExceptionHandlerServer::Delegate {
     snapshot.Initialize(process, ProcessSuspensionState::kSuspended);
     snapshot.InitializeException(exception_information_address);
     EXPECT_TRUE(snapshot.Exception());
-    EXPECT_EQ(0, snapshot.Exception()->Exception());
-    EXPECT_EQ(0, snapshot.Exception()->ExceptionAddress());
+    EXPECT_EQ(0x517a7ed, snapshot.Exception()->Exception());
 
     // Verify the dump was captured at the expected location with some slop
     // space.
@@ -203,6 +202,9 @@ class SimulateDelegate : public ExceptionHandlerServer::Delegate {
     EXPECT_LT(snapshot.Exception()->Context()->InstructionPointer(),
               dump_near_ + kAllowedOffset);
 
+    EXPECT_EQ(snapshot.Exception()->Context()->InstructionPointer(),
+              snapshot.Exception()->ExceptionAddress());
+
     SetEvent(completed_test_event_);
 
     return 0;