[clang] Support [[clang::lifetime_capture_by(X)]] in Plain Containers (PR #204361)

[Kashika Akhouri via cfe-commits]

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@@ -11,13 +12,28 @@ void captureInt(const int &i [[clang::lifetime_capture_by(x)]], X &x);
 void captureRValInt(int &&i [[clang::lifetime_capture_by(x)]], X &x);
 void noCaptureInt(int i [[clang::lifetime_capture_by(x)]], X &x);
 
-void use() {
-  int local;
-  captureInt(1, // expected-warning {{object whose reference is captured by 'x' will be destroyed at the end of the full-expression}}
-            x);
+void temporary_int_capture() {
+  captureInt(1,x); // expected-warning {{object whose reference is captured by 'x' will be destroyed at the end of the full-expression}}
+                   // cfg-warning at -1 {{temporary object does not live long enough}}
+                   // cfg-note at -2 {{destroyed here}}
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kashika0112 wrote:

Done, I have used `\` instead of offsets throughout the test file.

https://github.com/llvm/llvm-project/pull/204361