Rewire redecl chains if an element gets unloaded.

(cherry picked from commit e4db204d008f53aaecd6994f74a232703e061e59)
Pass the .L-ed transaction to actOnxCommand; last transaction might be wrong.

(cherry picked from commit e5dee9abe42e97209c175878a6c677a059222312)
Write empty keys for PCMs that are in the PCH.

(cherry picked from commit c562a7a79547aeb17382e01175c3a54045f702d8)
Prevent recursive comp in TVirtualStreamerInfo::Factory()

(cherry picked from commit a5fd93c306aefd6b24f3ee716f62f6487e6a50f5)
Check before Load() to prevent error message.

(cherry picked from commit 554b88813112baa227a53115694044d8fa8e23b5)
Substitute member types to Double32_t for templates.

(cherry picked from commit c3d391f6129062ae81bc2d89318229db51c8a691)
Use canonical Decls as key for "do not desugar"; may have dupe Type*s.

(cherry picked from commit 97119a8795f76d9693b24658982c59f25f0336d0)
PCH has partial names (include/TObject.h), use them for full paths.

(cherry picked from commit 7e31f48303236c04d3335da5f55928b58fc209a7)
Do not read the source file to emit annotations.

(cherry picked from commit 31ae8e339ab4947cf9193d484185653b69204e4e)
Do not read the file to determine its name!

(cherry picked from commit 5a43f6c1214b8db8579d67d2ee9833c1d80fb487)
Close the file handle if the content comes from a PC[HM].

(cherry picked from commit f14d221b14ebdf765773acb796b8f4c7564d993f)
Lookup::Named() can return ambiguity. Fixes PyROOT tests.