Xcode: Add frameworks search paths from link dependeny closure (#13397)

The Xcode generator produces FRAMEWORK_SEARCH_PATHS from:

(1) Include directories of the form /path/to/Foo.framework become
    -F/path/to so '#include <Foo/H>' can find H in the framework.

(2) Linked frameworks of the form /path/to/Foo.framework become
    -F/path/to -framework Foo so the linker can find the framework.

Originally commit 82bb6fae (add framework support to FIND_FILE,
2005-12-27) added these and used the (then current) old-style link
dependency analysis results to get the frameworks.  Later a second
setting was added by commit 2ed6191f (add initial xcode framework stuff,
2007-05-08) to transform -F/path/to linker options produced by the old
link line generation into entries appended to FRAMEWORK_SEARCH_PATHS.
Then commit 96fd5909 (Implement linking with paths to library files,
2008-01-22) updated the second setting to directly use the results of
full modern link dependency analysis, but forgot to remove the use of
old-style link results from the original setting location.

The two settings worked together for a while, with the second one
appending to the first.  Then commit f33a27ab (Generate native Xcode 3.0
and 3.1 projects, 2009-06-29) changed the internal representation format
produced by the first setting but did not update the second setting to
append to the new representation.  As a result, if the first setting
added any paths (usually via the old-style link analysis) then the
second setting containing the modern link analysis results would not be
applied at all.

Fix this by removing use of the old-style link analysis results.
Replace it using the modern link dependencies and remove the second
setting altogether.  Now all values for FRAMEWORK_SEARCH_PATHS are
collected in one place so no special append logic is needed.

Source/cmGlobalXCodeGenerator.cxx

@@ -1997,15 +1997,20 @@ void cmGlobalXCodeGenerator::CreateBuildSettings(cmTarget& target,
       dirs.Add(incpath.c_str());
       }
     }
-  std::vector<std::string>& frameworks = target.GetFrameworks();
-  if(frameworks.size())
+  if(target.GetType() != cmTarget::OBJECT_LIBRARY &&
+     target.GetType() != cmTarget::STATIC_LIBRARY)
     {
-    for(std::vector<std::string>::iterator fmIt = frameworks.begin();
-        fmIt != frameworks.end(); ++fmIt)
+    // Add framework search paths needed for linking.
+    if(cmComputeLinkInformation* cli = target.GetLinkInformation(configName))
       {
-      if(emitted.insert(*fmIt).second)
+      std::vector<std::string> const& fwDirs = cli->GetFrameworkPaths();
+      for(std::vector<std::string>::const_iterator fdi = fwDirs.begin();
+          fdi != fwDirs.end(); ++fdi)
         {
-        fdirs.Add(this->XCodeEscapePath(fmIt->c_str()).c_str());
+        if(emitted.insert(*fdi).second)
+          {
+          fdirs.Add(this->XCodeEscapePath(fdi->c_str()).c_str());
+          }
         }
       }
     }
@@ -2691,25 +2696,6 @@ void cmGlobalXCodeGenerator
                                       linkDirs.c_str(), configName);
     }
 
-    // add the framework search paths
-    {
-    const char* sep = "";
-    std::string fdirs;
-    std::vector<std::string> const& fwDirs = cli.GetFrameworkPaths();
-    for(std::vector<std::string>::const_iterator fdi = fwDirs.begin();
-        fdi != fwDirs.end(); ++fdi)
-      {
-      fdirs += sep;
-      sep = " ";
-      fdirs += this->XCodeEscapePath(fdi->c_str());
-      }
-    if(!fdirs.empty())
-      {
-      this->AppendBuildSettingAttribute(target, "FRAMEWORK_SEARCH_PATHS",
-                                        fdirs.c_str(), configName);
-      }
-    }
-
     // now add the link libraries
     {
     std::string linkLibs;