In a following patch, all DevTools moz.build files will use DevToolsModules to
install JS modules at a path that corresponds directly to their source tree
location. Here we rewrite all require and import calls to match the new
location that these files are installed to.
Move major DevTools files to new directories using the following steps:
hg mv browser/devtools devtools/client
hg mv toolkit/devtools/server devtools/server
hg mv toolkit/devtools devtools/shared
No other changes are made.
