fix(elements): strict null checks (#24861)
fix(elements): strict null checks (#24861)

PR Close #24861

ultrasonicsoft/angular,ocombe/angular,Toxicable/angular,mprobst/angular,brandonroberts/angular,ultrasonicsoft/angular,Brocco/angular,gdi2290/angular,shairez/angular,hansl/angular,filipesilva/angular,sarunint/angular,gdi2290/angular,vikerman/angular,StephenFluin/angular,filipesilva/angular,wKoza/angular,angular/angular,ocombe/angular,ValtoFrameworks/Angular-2,matsko/angular,alxhub/angular,blesh/angular,hansl/angular,mgechev/angular,IgorMinar/angular,alxhub/angular,JiaLiPassion/angular,mhevery/angular,juristr/angular,trshafer/angular,manekinekko/angular,mgechev/angular,matsko/angular,kegluneq/angular,angular-indonesia/angular,kara/angular,jasonaden/angular,Brocco/angular,ultrasonicsoft/angular,alxhub/angular,vikerman/angular,snaptech/angular,alexeagle/angular,mgechev/angular,ocombe/angular,brandonroberts/angular,sarunint/angular,sarunint/angular,Toxicable/angular,mprobst/angular,filipesilva/angular,matsko/angular,juristr/angular,filipesilva/angular,petebacondarwin/angular,manekinekko/angular,trshafer/angular,angular/angular,mgechev/angular,gkalpak/angular,gnomeontherun/angular,manekinekko/angular,shairez/angular,JiaLiPassion/angular,gkalpak/angular,matsko/angular,wKoza/angular,mprobst/angular,gkalpak/angular,angular-indonesia/angular,sarunint/angular,gnomeontherun/angular,brandonroberts/angular,alexeagle/angular,manekinekko/angular,wKoza/angular,mlaval/angular,trshafer/angular,brandonroberts/angular,angular/angular,mlaval/angular,juristr/angular,filipesilva/angular,snaptech/angular,hansl/angular,ultrasonicsoft/angular,mprobst/angular,jasonaden/angular,trshafer/angular,mprobst/angular,IgorMinar/angular,alexeagle/angular,Toxicable/angular,mhevery/angular,blesh/angular,kegluneq/angular,gkalpak/angular,mgechev/angular,kara/angular,jasonaden/angular,IdeaBlade/angular,JiaLiPassion/angular,petebacondarwin/angular,gdi2290/angular,brandonroberts/angular,alexeagle/angular,sarunint/angular,IgorMinar/angular,ocombe/angular,angular-indonesia/angular,wKoza/angular,Toxicable/angular,angular/angular,snaptech/angular,StephenFluin/angular,blesh/angular,Toxicable/angular,alxhub/angular,kara/angular,ocombe/angular,IdeaBlade/angular,juristr/angular,blesh/angular,sarunint/angular,kegluneq/angular,JiaLiPassion/angular,ValtoFrameworks/Angular-2,juristr/angular,snaptech/angular,ValtoFrameworks/Angular-2,IgorMinar/angular,mlaval/angular,ValtoFrameworks/Angular-2,wKoza/angular,manekinekko/angular,mprobst/angular,brandonroberts/angular,vikerman/angular,ocombe/angular,mhevery/angular,alxhub/angular,petebacondarwin/angular,ultrasonicsoft/angular,Brocco/angular,trshafer/angular,mhevery/angular,hansl/angular,IdeaBlade/angular,Brocco/angular,vikerman/angular,alexeagle/angular,IdeaBlade/angular,matsko/angular,shairez/angular,StephenFluin/angular,mhevery/angular,kara/angular,gdi2290/angular,vikerman/angular,jasonaden/angular,jasonaden/angular,IgorMinar/angular,blesh/angular,kegluneq/angular,ultrasonicsoft/angular,kegluneq/angular,jasonaden/angular,StephenFluin/angular,wKoza/angular,gdi2290/angular,snaptech/angular,kegluneq/angular,vikerman/angular,Toxicable/angular,shairez/angular,mlaval/angular,IdeaBlade/angular,kara/angular,alexeagle/angular,gnomeontherun/angular,kara/angular,gdi2290/angular,shairez/angular,Brocco/angular,manekinekko/angular,ValtoFrameworks/Angular-2,gnomeontherun/angular,snaptech/angular,IgorMinar/angular,petebacondarwin/angular,angular-indonesia/angular,petebacondarwin/angular,hansl/angular,juristr/angular,trshafer/angular,mlaval/angular,Brocco/angular,mhevery/angular,StephenFluin/angular,hansl/angular,petebacondarwin/angular