Parse UTF-16 surrogates pairs for calculating pattern's position (#11915

)

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## Summary of the Pull Request

Properly handle UTF-16 surrogates when calculating the position of matched pattern.

Fix #8709

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## References
https://github.com/microsoft/terminal/blob/b88ffb21b0725331877ba76bac5a79a4c21eaa03/src/buffer/out/search.cpp#L335-L339

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## PR Checklist
* [ ] Closes #8709
* [x] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [ ] Documentation updated. If checked, please file a pull request on [our docs repo](https://github.com/MicrosoftDocs/terminal) and link it here: #xxx
* [ ] Schema updated.
* [ ] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx

<!-- Provide a more detailed description of the PR, other things fixed or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments
use `Utf16Parser::Parse` to handle code points from U+010000 to U+10FFFF in UTF-16.

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## Validation Steps Performed

![image](https://user-images.githubusercontent.com/1068203/145421736-c842c7d4-0136-42d0-ad72-f004f58d9e3b.png)

also the case by @mas90  #8709 (comment):

![image](https://user-images.githubusercontent.com/1068203/145420264-3fe220b4-42c5-44ac-aa94-4e604b164ed3.png)

src/buffer/out/textBuffer.cpp

@@ -8,6 +8,7 @@
 
 #include "../types/inc/utils.hpp"
 #include "../types/inc/convert.hpp"
+#include "../../types/inc/Utf16Parser.hpp"
 #include "../../types/inc/GlyphWidth.hpp"
 
 #pragma hdrstop
@@ -2585,16 +2586,17 @@ PointTree TextBuffer::GetPatterns(const size_t firstRow, const size_t lastRow) c
             // match and the previous match, so we use the size of the prefix
             // along with the size of the match to determine the locations
             size_t prefixSize = 0;
-
-            for (const auto ch : i->prefix().str())
+            for (const std::vector<wchar_t> parsedGlyph : Utf16Parser::Parse(i->prefix().str()))
             {
-                prefixSize += IsGlyphFullWidth(ch) ? 2 : 1;
+                const std::wstring_view glyph{ parsedGlyph.data(), parsedGlyph.size() };
+                prefixSize += IsGlyphFullWidth(glyph) ? 2 : 1;
             }
             const auto start = lenUpToThis + prefixSize;
             size_t matchSize = 0;
-            for (const auto ch : i->str())
+            for (const std::vector<wchar_t> parsedGlyph : Utf16Parser::Parse(i->str()))
             {
-                matchSize += IsGlyphFullWidth(ch) ? 2 : 1;
+                const std::wstring_view glyph{ parsedGlyph.data(), parsedGlyph.size() };
+                matchSize += IsGlyphFullWidth(glyph) ? 2 : 1;
             }
             const auto end = start + matchSize;
             lenUpToThis = end;